ATL: IDA - Advisories

[AlphaToOmega]

000
WTNT34 KNHC 261445
TCPAT4

BULLETIN
Tropical Depression Nine Advisory Number 1
NWS National Hurricane Center Miami FL AL092021
1100 AM EDT Thu Aug 26 2021

...TROPICAL DEPRESSION FORMS OVER THE WEST-CENTRAL CARIBBEAN SEA...
...TROPICAL STORM WARNINGS ISSUED FOR THE CAYMAN ISLANDS AND
PORTIONS OF WESTERN CUBA...


SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...16.9N 79.2W
ABOUT 115 MI...180 KM SSW OF NEGRIL JAMAICA
ABOUT 210 MI...340 KM SE OF GRAND CAYMAN
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of the Cayman Islands has issued a Tropical Storm
Warning for the Cayman Islands, including Grand Cayman, Little
Cayman, and Cayman Brac.

The government of Cuba has issued a Tropical Storm Warning for the
Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Cayman Islands
* Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

Interests elsewhere in central and western Cuba, in the northern
Yucatan Peninsula, and along the northern U.S. Gulf coast should
monitor the progress of this system.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 1100 AM EDT (1500 UTC), the center of Tropical Depression Nine
was located near latitude 16.9 North, longitude 79.2 West. The
depression is moving toward the northwest near 13 mph (20 km/h),
and this general motion should continue over the next few days. On
the forecast track, the center of the depression will pass near
of over the Cayman Islands tonight, the Isle of Youth and Western
Cuba Friday, and move over the southeastern and central Gulf of
Mexico Friday night and Saturday. The system is forecast to
approach the U.S. northern Gulf coast on Sunday.

Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Steady strengthening is forecast during the next few days. The
depression is expected to become a tropical storm tonight, and
become a hurricane when it is near western Cuba or over the
southeastern Gulf of Mexico. Additional strengthening is likely
over the Gulf of Mexico and the system could be near major
hurricane strength when it approaches the northern Gulf coast.

The estimated minimum central pressure is 1005 mb (29.68 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Depression Nine can be found in the
Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO
header WTNT44 KNHC, and on the web at
hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 2 to 4 feet above normal tide levels in areas of onshore
flow along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

WIND: Tropical storm conditions are expected in the Cayman
Islands tonight, and are expected to reach the Isle of Youth and
portions of western Cuba in the warning area on Friday.

RAINFALL: The depression is expected to produce total rainfall
accumulations of 6 to 10 inches with maximum totals of 15 inches
across Jamaica. Rainfall totals of 8 to 12 inches with isolated
maximum amounts of 20 inches are expected across the Cayman
Islands, western Cuba, including the Isle of Youth and the northeast
portions of the Yucatan Peninsula. These rainfall amounts may
produce life-threatening flash floods and mudslides.

Rainfall from this system is likely to begin impacting portions
of the central U.S. Gulf Coast by early Sunday.

SURF: Swells generated by this system will begin affecting Jamaica,
the Cayman Islands and Cuba tonight and Friday. These swells are
likely to cause life-threatening surf and rip current conditions.
Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 200 PM EDT.
Next complete advisory at 500 PM EDT.

$$
Forecaster Brown

000
WTNT24 KNHC 261444
TCMAT4

TROPICAL DEPRESSION NINE FORECAST/ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092021
1500 UTC THU AUG 26 2021

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

THE GOVERNMENT OF THE CAYMAN ISLANDS HAS ISSUED A TROPICAL STORM
WARNING FOR THE CAYMAN ISLANDS...INCLUDING GRAND CAYMAN...LITTLE
CAYMAN...AND CAYMAN BRAC.

THE GOVERNMENT OF CUBA HAS ISSUED A TROPICAL STORM WARNING FOR THE
CUBAN PROVINCES OF MATANZAS...MAYABEQUE...HAVANA...ARTEMISA...PINAR
DEL RIO...AND THE ISLE OF YOUTH.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* CAYMAN ISLANDS
* CUBAN PROVINCES OF MATANZAS...MAYABEQUE...HAVANA...ARTEMISA...
PINAR DEL RIO...AND THE ISLE OF YOUTH

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA WITHIN 36 HOURS.

INTERESTS ELSEWHERE IN CENTRAL AND WESTERN CUBA...IN THE NORTHERN
YUCATAN PENINSULA...AND ALONG THE NORTHERN U.S. GULF COAST SHOULD
MONITOR THE PROGRESS OF THIS SYSTEM.

TROPICAL DEPRESSION CENTER LOCATED NEAR 16.9N 79.2W AT 26/1500Z
POSITION ACCURATE WITHIN 40 NM

PRESENT MOVEMENT TOWARD THE NORTHWEST OR 325 DEGREES AT 11 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1005 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 16.9N 79.2W AT 26/1500Z
AT 26/1200Z CENTER WAS LOCATED NEAR 16.4N 79.0W

FORECAST VALID 27/0000Z 18.2N 80.4W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 60NE 40SE 0SW 60NW.

FORECAST VALID 27/1200Z 20.3N 82.0W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 80NE 50SE 20SW 60NW.

FORECAST VALID 28/0000Z 22.5N 83.9W...OVER WESTERN CUBA
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 30NE 0SE 0SW 0NW.
34 KT... 90NE 60SE 40SW 70NW.

FORECAST VALID 28/1200Z 24.4N 86.0W...OVER SOUTHEASTERN GULF
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 20NE 20SE 0SW 20NW.
50 KT... 40NE 40SE 30SW 40NW.
34 KT...110NE 80SE 60SW 90NW.

FORECAST VALID 29/0000Z 26.1N 88.1W
MAX WIND 80 KT...GUSTS 100 KT.
50 KT... 50NE 50SE 30SW 50NW.
34 KT...130NE 110SE 60SW 110NW.

FORECAST VALID 29/1200Z 27.7N 90.0W
MAX WIND 95 KT...GUSTS 115 KT.
50 KT... 50NE 50SE 30SW 50NW.
34 KT...140NE 130SE 70SW 120NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM
ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY

OUTLOOK VALID 30/1200Z 30.5N 92.0W...INLAND
MAX WIND 70 KT...GUSTS 85 KT.

OUTLOOK VALID 31/1200Z 33.7N 91.2W...INLAND
MAX WIND 30 KT...GUSTS 40 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.9N 79.2W

INTERMEDIATE PUBLIC ADVISORY...WTNT34 KNHC/MIATCPAT4...AT 26/1800Z

NEXT ADVISORY AT 26/2100Z

$$
FORECASTER BROWN

[cycloneye]

BULLETIN
Tropical Depression Nine Advisory Number 1
NWS National Hurricane Center Miami FL AL092021
1100 AM EDT Thu Aug 26 2021

...TROPICAL DEPRESSION FORMS OVER THE WEST-CENTRAL CARIBBEAN SEA...
...TROPICAL STORM WARNINGS ISSUED FOR THE CAYMAN ISLANDS AND
PORTIONS OF WESTERN CUBA...


SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...16.9N 79.2W
ABOUT 115 MI...180 KM SSW OF NEGRIL JAMAICA
ABOUT 210 MI...340 KM SE OF GRAND CAYMAN
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of the Cayman Islands has issued a Tropical Storm
Warning for the Cayman Islands, including Grand Cayman, Little
Cayman, and Cayman Brac.

The government of Cuba has issued a Tropical Storm Warning for the
Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Cayman Islands
* Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

Interests elsewhere in central and western Cuba, in the northern
Yucatan Peninsula, and along the northern U.S. Gulf coast should
monitor the progress of this system.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 1100 AM EDT (1500 UTC), the center of Tropical Depression Nine
was located near latitude 16.9 North, longitude 79.2 West. The
depression is moving toward the northwest near 13 mph (20 km/h),
and this general motion should continue over the next few days. On
the forecast track, the center of the depression will pass near
of over the Cayman Islands tonight, the Isle of Youth and Western
Cuba Friday, and move over the southeastern and central Gulf of
Mexico Friday night and Saturday. The system is forecast to
approach the U.S. northern Gulf coast on Sunday.

Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Steady strengthening is forecast during the next few days. The
depression is expected to become a tropical storm tonight, and
become a hurricane when it is near western Cuba or over the
southeastern Gulf of Mexico. Additional strengthening is likely
over the Gulf of Mexico and the system could be near major
hurricane strength when it approaches the northern Gulf coast.

The estimated minimum central pressure is 1005 mb (29.68 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Depression Nine can be found in the
Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO
header WTNT44 KNHC, and on the web at
hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 2 to 4 feet above normal tide levels in areas of onshore
flow along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

WIND: Tropical storm conditions are expected in the Cayman
Islands tonight, and are expected to reach the Isle of Youth and
portions of western Cuba in the warning area on Friday.

RAINFALL: The depression is expected to produce total rainfall
accumulations of 6 to 10 inches with maximum totals of 15 inches
across Jamaica. Rainfall totals of 8 to 12 inches with isolated
maximum amounts of 20 inches are expected across the Cayman
Islands, western Cuba, including the Isle of Youth and the northeast
portions of the Yucatan Peninsula. These rainfall amounts may
produce life-threatening flash floods and mudslides.

Rainfall from this system is likely to begin impacting portions
of the central U.S. Gulf Coast by early Sunday.

SURF: Swells generated by this system will begin affecting Jamaica,
the Cayman Islands and Cuba tonight and Friday. These swells are
likely to cause life-threatening surf and rip current conditions.
Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 200 PM EDT.
Next complete advisory at 500 PM EDT.

$$
Forecaster Brown


Tropical Depression Nine Discussion Number 1
NWS National Hurricane Center Miami FL AL092021
1100 AM EDT Thu Aug 26 2021

Early morning visible satellite imagery shows that the circulation
associated with the area of low pressure over west-central
Caribbean Sea has become better defined. There has also been an
increase in the organization of the associated convective activity,
and based on consensus Dvorak T-numbers of 2.0 from TAFB and SAB,
advisories are being initiated on a tropical depression. The initial
intensity is set at 30 kt, in agreement with the subjective
satellite estimates. The official reporting station in Kingston,
Jamaica, has reported sustained winds of 25 kt with gusts to 35 kt
during the past couple of hours. An Air Force Reserve
reconnaissance aircraft is scheduled to be in the system later this
afternoon to provide more information on the system's structure
and intensity.

The depression is moving northwestward or 325/11 kt, however the
initial motion is a bit more uncertain than normal since the low-
level center has only recently formed. The cyclone is forecast
to move steadily northwestward around the southwestern portion of a
deep-layer ridge centered over the western Atlantic. This track
should bring the center near or over western Cuba late Friday,
over the southeastern and central Gulf of Mexico Friday night and
Saturday, and have the center approach the northern Gulf coast on
Sunday. The track guidance is in relatively good agreement, however
the average NHC track forecast error at day 4 is around 175 miles,
so users should not focus on the details of the long range track
forecast. Some shifts in the track are likely until the system
consolidates and becomes better defined. The NHC track is near the
various consensus model aids and is in best agreement with the GFS
ensemble mean.

The depression will be moving over the high ocean heat content
waters of the northwestern Caribbean Sea during the next 24-36
hours. This, in combination with low vertical wind shear and a
moist environment, should allow for steady strengthening. The
depression is forecast to become a tropical storm later today or
tonight, and could approach hurricane strength as it passes near
or over western Cuba. Once the system moves into the Gulf of
Mexico, conditions are expected to be conducive for additional
strengthening, and rapid intensification is explicitly shown in
the NHC forecast between 48 and 72 hours. The NHC intensity forecast
brings the system near major hurricane strength when it approaches
the northern Gulf coast on Sunday. This forecast is supported by the
HWRF and CTCI models, and the GFS, ECMWF, and UKMET global model
guidance, which all significantly deepen the cyclone over the Gulf
of Mexico. As a result, there is higher-than-normal confidence
that a strengthening tropical cyclone will be moving over the Gulf
this weekend.

Key Messages:

1. Tropical storm conditions are likely in portions of the Cayman
Islands tonight and western Cuba Friday and Friday night, with
dangerous storm surge possible in portions of western Cuba,
including the Isle of Youth, in areas of onshore flow.

2. The system is expected to produce life-threatening heavy rains,
flash flooding and mudslides across Jamaica, the Cayman Islands,
western Cuba, including the Isle of Youth and northeastern portions
of the Yucatan Peninsula.

3. This system is forecast to approach the northern Gulf Coast at or
near major hurricane intensity on Sunday, although the forecast
uncertainty is larger than usual since the system is just forming.
There is a risk of life-threatening storm surge, damaging
hurricane-force winds, and heavy rainfall Sunday and Monday along
the northern Gulf Coast from the Florida Panhandle to the upper
Texas coast, with the greatest risk along the coast of Louisiana.
Interests in these areas should closely monitor the progress of this
system and ensure they have their hurricane plan in place.

FORECAST POSITIONS AND MAX WINDS

INIT 26/1500Z 16.9N 79.2W 30 KT 35 MPH
12H 27/0000Z 18.2N 80.4W 35 KT 40 MPH
24H 27/1200Z 20.3N 82.0W 45 KT 50 MPH
36H 28/0000Z 22.5N 83.9W 55 KT 65 MPH...INLAND
48H 28/1200Z 24.4N 86.0W 65 KT 75 MPH...OVER WATER
60H 29/0000Z 26.1N 88.1W 80 KT 90 MPH
72H 29/1200Z 27.7N 90.0W 95 KT 110 MPH
96H 30/1200Z 30.5N 92.0W 70 KT 80 MPH...INLAND
120H 31/1200Z 33.7N 91.2W 30 KT 35 MPH...INLAND

$$
Forecaster Brown

[cycloneye]

BULLETIN
Tropical Depression Nine Intermediate Advisory Number 1A
NWS National Hurricane Center Miami FL AL092021
200 PM EDT Thu Aug 26 2021

...TROPICAL DEPRESSION EXPECTED TO STRENGTHEN OVER THE NORTHWESTERN
CARIBBEAN SEA...
...AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT EN ROUTE...


SUMMARY OF 200 PM EDT...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...17.5N 79.5W
ABOUT 95 MI...155 KM SW OF NEGRIL JAMAICA
ABOUT 165 MI...270 KM SE OF GRAND CAYMAN
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Cayman Islands
* Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

Interests elsewhere in central and western Cuba, in the northern
Yucatan Peninsula, and along the northern U.S. Gulf coast should
monitor the progress of this system.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 200 PM EDT (1800 UTC), the center of Tropical Depression Nine was
located near latitude 17.5 North, longitude 79.5 West. The
depression is moving toward the northwest near 13 mph (20 km/h), and
this general motion should continue over the next few days. On the
forecast track, the center of the depression will pass near or over
the Cayman Islands tonight, the Isle of Youth and western Cuba
Friday, and over the southeastern and central Gulf of Mexico Friday
night and Saturday. The system is forecast to approach the U.S.
northern Gulf coast on Sunday.

Maximum sustained winds are near 35 mph (55 km/h) with higher
gusts. Steady strengthening is forecast during the next few days.
The depression is expected to become a tropical storm tonight, and
become a hurricane when it is near western Cuba or over the
southeastern Gulf of Mexico. Additional strengthening is likely
over the Gulf of Mexico, and the system could be near major
hurricane strength when it approaches the northern Gulf coast.

The estimated minimum central pressure is 1005 mb (29.68 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Depression Nine can be found in the
Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO
header WTNT44 KNHC, and on the web at
hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 2 to 4 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

WIND: Tropical storm conditions are expected in the Cayman
Islands tonight, and are expected to reach the Isle of Youth and
portions of western Cuba in the warning area on Friday.

RAINFALL: The depression is expected to produce total rainfall
accumulations of 6 to 10 inches with maximum totals of 15 inches
across Jamaica. Rainfall totals of 8 to 12 inches with isolated
maximum amounts of 20 inches are expected across the Cayman
Islands, western Cuba, including the Isle of Youth, and the
northeast portions of the Yucatan Peninsula. These rainfall amounts
may produce life-threatening flash floods and mudslides.

Rainfall from this system is likely to begin impacting portions
of the central U.S. Gulf Coast by early Sunday.

SURF: Swells generated by this system will begin affecting Jamaica,
the Cayman Islands and Cuba tonight and Friday. These swells are
likely to cause life-threatening surf and rip current conditions.
Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next complete advisory at 500 PM EDT.

$$
Forecaster Brown

[cycloneye]

BULLETIN
Tropical Depression Nine Advisory Number 2
NWS National Hurricane Center Miami FL AL092021
500 PM EDT Thu Aug 26 2021

...DEPRESSION EXPECTED TO STRENGTHEN INTO A TROPICAL STORM SOON...
...AIR FORCE HURRICANE HUNTER AIRCRAFT CURRENTLY INVESTIGATING THE
SYSTEM...


SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...18.0N 79.8W
ABOUT 100 MI...160 KM WSW OF NEGRIL JAMAICA
ABOUT 130 MI...205 KM SE OF GRAND CAYMAN
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Cayman Islands
* Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

Interests elsewhere in central and western Cuba, in the northern
Yucatan Peninsula, and along the northern U.S. Gulf coast should
monitor the progress of this system. Watches may be required for a
portion of the northern Gulf coast later tonight or Friday morning.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 500 PM EDT (2100 UTC), the center of Tropical Depression Nine was
located near latitude 18.0 North, longitude 79.8 West. The
depression is moving toward the northwest near 14 mph (22 km/h),
and this general motion should continue over the next few days. On
the forecast track, the center of the depression will pass near or
over the Cayman Islands tonight, the Isle of Youth and western Cuba
Friday, and over the southeastern and central Gulf of Mexico Friday
night and Saturday. The system is forecast to approach the U.S.
northern Gulf coast on Sunday.

Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Steady strengthening is forecast during the next few days. The
depression is expected to become a tropical storm tonight, and
become a hurricane when it is near western Cuba or over the
southeastern Gulf of Mexico. Additional strengthening is likely
over the Gulf of Mexico, and the system could be near major
hurricane strength when it approaches the northern Gulf coast.

The estimated minimum central pressure from Air Force Reserve
reconnaissance data is 1006 mb (29.71 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Depression Nine can be found in the
Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO
header WTNT44 KNHC, and on the web at
hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 2 to 4 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

WIND: Tropical storm conditions are expected in the Cayman
Islands tonight, and are expected to reach the Isle of Youth and
portions of western Cuba in the warning area on Friday.

RAINFALL: The depression is expected to produce total rainfall
accumulations of 6 to 10 inches with maximum totals of 15 inches
across Jamaica. Rainfall totals of 8 to 12 inches with isolated
maximum amounts of 20 inches are expected across the Cayman Islands
and western Cuba, including the Isle of Youth. These rainfall
amounts may produce life-threatening flash floods and mudslides.

The depression may begin to bring rainfall and potential flooding
impacts to the central Gulf Coast by early Sunday.

SURF: Swells generated by this system will begin affect Jamaica,
the Cayman Islands and Cuba tonight and Friday. These swells are
likely to cause life-threatening surf and rip current conditions.
Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 800 PM EDT.
Next complete advisory at 1100 PM EDT.

$$
Forecaster Brown

Tropical Depression Nine Discussion Number 2
NWS National Hurricane Center Miami FL AL092021
500 PM EDT Thu Aug 26 2021

The overall satellite presentation of the tropical cyclone has
continued to gradually improve today. Visible imagery and very
recent observations from an Air Force Reserve reconnaissance
aircraft indicate that the circulation has continued to become
better defined. In addition, the convective activity has become a
little better organized in a band around the northeastern and
eastern portions of the circulation, and the system is likely near
tropical storm strength. However, the initial intensity remains 30
kt pending the aircraft fully sampling the eastern portion of the
circulation.

The initial motion estimate is northwestward or 325/12 kt. The 1200
UTC dynamical model guidance continues to take the system
northwestward around the southwestern side of well-established
deep-layer ridge over the western Atlantic. On the forecast track,
the system is expected to move over portions of western Cuba late
Friday, over the southeastern and central Gulf of Mexico on
Saturday, and approach the northern Gulf coast on Sunday. Although
the track guidance envelope has tightened this cycle, increasing
confidence in the overall forecast scenario, some shifts in the
track are still likely until the system consolidates and becomes
better defined. Users are reminded to not focus on the exact
forecast track as storm surge, wind, and rainfall hazards will
extend far from the center, and the average NHC track forecast error
at day 3 is around 120 miles. The lastest NHC track forecast is
close to the previous official forecast, and lies between the TCVA
and HCCA consensus aids.

There is some evidence of some light to moderate southerly shear
over the system, but with the cyclone moving over the high ocean
heat content waters of the northwestern Caribbean Sea the shear
should not hinder intensification, with steady strengthening
anticipated during the next 12 to 24 hours. Once the system moves
over the Gulf of Mexico, it will be traversing a warm eddy, and this
feature, combined with a favorable upper-level wind pattern and a
moist atmosphere, is likely to result in steady to rapid
strengthening on Saturday and Saturday night. The NHC intensity
forecast again brings the system to near major hurricane strength
when it approaches the northern Gulf coast on Sunday. This is
supported by the HWRF and CTCI models, and the global model guidance
that has consistently showed significant deepening of the system
over the Gulf of Mexico over the past several model cycles.
Therefore, as mentioned this morning, there is higher-than-normal
confidence that a strengthening tropical cyclone will be moving over
the Gulf of Mexico this weekend.

Key Messages:

1. Tropical storm conditions are expected in portions of the Cayman
Islands tonight and in portions of western Cuba and the Isle of
Youth Friday. Dangerous storm surge is possible Friday in portions
of western Cuba, including the Isle of Youth, in areas of onshore
flow.

2. Life-threatening heavy rains, flash flooding and mudslides are
expected across Jamaica, the Cayman Islands, and western Cuba,
including the Isle of Youth.

3. The system is forecast to approach the northern Gulf coast at or
near major hurricane intensity on Sunday, where there is an
increasing risk of life-threatening storm surge, damaging
hurricane-force winds, and heavy rainfall Sunday and Monday,
especially along the coast of Louisiana. Storm Surge and Hurricane
watches will likely be issued for a portion of this area later
tonight or Friday morning. Interests in these areas should closely
monitor the progress of this system and follow any advice given by
local officials.

FORECAST POSITIONS AND MAX WINDS

INIT 26/2100Z 18.0N 79.8W 30 KT 35 MPH
12H 27/0600Z 19.7N 81.0W 45 KT 50 MPH
24H 27/1800Z 21.7N 82.8W 55 KT 65 MPH...INLAND
36H 28/0600Z 23.7N 84.8W 60 KT 70 MPH...OVER WATER
48H 28/1800Z 25.6N 87.0W 70 KT 80 MPH
60H 29/0600Z 27.2N 88.8W 85 KT 100 MPH
72H 29/1800Z 28.9N 90.4W 95 KT 110 MPH
96H 30/1800Z 31.9N 91.4W 50 KT 60 MPH...INLAND
120H 31/1800Z 34.6N 90.0W 25 KT 30 MPH...INLAND

$$
Forecaster Brown

[AlphaToOmega]

336
WTNT64 KNHC 262116
TCUAT4

Tropical Storm Ida Tropical Cyclone Update
NWS National Hurricane Center Miami FL AL092021
520 PM EDT Thu Aug 26 2021

...AIR FORCE PLANE FINDS DEPRESSION A TROPICAL STORM...

Air Force Reserve hurricane hunter aircraft data indicate that the
depression has strengthened to Tropical Storm Ida. The maximum
sustained winds are estimated to be 40 mph (65 km/h) with higher
gusts.


SUMMARY OF 520 PM EDT...2120 UTC...INFORMATION
----------------------------------------------
LOCATION...18.0N 79.8W
ABOUT 100 MI...160 KM WSW OF NEGRIL JAMAICA
ABOUT 130 MI...205 KM SE OF GRAND CAYMAN
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES

$$
Forecaster Brown

[cycloneye]

BULLETIN
Tropical Storm Ida Intermediate Advisory Number 2A
NWS National Hurricane Center Miami FL AL092021
800 PM EDT Thu Aug 26 2021

...IDA FORECAST TO STRENGTHEN...
...TROPICAL STORM CONDITIONS EXPECTED IN THE CAYMAN ISLANDS
LATER TONIGHT AND ACROSS WESTERN CUBA ON FRIDAY...


SUMMARY OF 800 PM EDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...18.0N 80.1W
ABOUT 115 MI...185 KM SE OF GRAND CAYMAN
ABOUT 120 MI...195 KM W OF NEGRIL JAMAICA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...NW OR 310 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...
* Cayman Islands
* Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

Interests elsewhere in central and western Cuba, in the northern
Yucatan Peninsula, and along the northern U.S. Gulf coast should
monitor the progress of this system. Watches may be required for a
portion of the northern Gulf coast later tonight or Friday morning.

For storm information specific to your area, please monitor
products issued by your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 800 PM EDT (0000 UTC), the center of Tropical Storm Ida was
located near latitude 18.0 North, longitude 80.1 West. The storm is
moving toward the northwest near 13 mph (20 km/h), and this general
motion should continue over the next few days. On the forecast
track, the center of Ida will pass near or over the Cayman Islands
tonight, the Isle of Youth and western Cuba Friday, and over the
southeastern and central Gulf of Mexico Friday night and Saturday.
The system is forecast to approach the U.S. northern Gulf coast on
Sunday.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Steady strengthening is forecast during the next few days. Ida is
forecast to become a hurricane when it is near western Cuba with
additional strengthening expected while it moves over the Gulf of
Mexico. Ida could be near major hurricane strength when it
approaches the northern Gulf coast.

Tropical-storm-force winds extend outward up to 70 miles (110 km)
north of the center.

The estimated minimum central pressure based on Air Force Reserve
reconnaissance data is 1006 mb (29.71 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Storm Ida can be found in the
Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO
header WTNT44 KNHC, and on the web at
hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 2 to 4 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

WIND: Tropical storm conditions are expected in the Cayman Islands
tonight, and are expected to reach the Isle of Youth and portions of
western Cuba in the warning area on Friday.

RAINFALL: Ida is expected to produce total rainfall accumulations
of 6 to 10 inches with maximum totals of 15 inches across Jamaica.
Rainfall totals of 8 to 12 inches with isolated maximum amounts of
20 inches are expected across the Cayman Islands and western Cuba,
including the Isle of Youth. These rainfall amounts may produce
life-threatening flash floods and mudslides.

Ida may begin to bring rainfall and potential flooding impacts to
the central Gulf Coast by early Sunday.

SURF: Swells generated by this system will affect Jamaica, the
Cayman Islands and Cuba tonight and Friday. These swells are likely
to cause life-threatening surf and rip current conditions. Please
consult products from your local weather office.


NEXT ADVISORY
-------------
Next complete advisory at 1100 PM EDT.

$$
Forecaster Cangialosi

[cycloneye]

BULLETIN
Tropical Storm Ida Advisory Number 3
NWS National Hurricane Center Miami FL AL092021
1100 PM EDT Thu Aug 26 2021

...HURRICANE WATCHES HAVE BEEN ISSUED FOR PORTIONS OF THE NORTHERN
GULF COAST...


SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...18.6N 80.5W
ABOUT 65 MI...105 KM SE OF GRAND CAYMAN
ABOUT 365 MI...585 KM SE OF THE WESTERN TIP OF CUBA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The Storm Surge Watch has been issued from Sabine Pass to the
Alabama/Florida border including Vermilion Bay, Lake Borgne, Lake
Pontchartrain, Lake Maurepas, and Mobile Bay

A Hurricane Watch has been issued from Cameron, Louisiana eastward
to the Mississippi/Alabama border, including Lake Pontchartrain,
Lake Maurepas, and metropolitan New Orleans.

A Tropical Storm Watch has been issued from the Mississippi/Alabama
border to the Alabama/Florida border.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Watch is in effect for...
* Sabine Pass to Alabama/Florida border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, Lake Maurepas, and
Mobile Bay

A Hurricane Watch is in effect for...
* Cameron, Louisiana to the Mississippi/Alabama border
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Tropical Storm Warning is in effect for...
* Cayman Islands
* Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.
For a depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere in central and western Cuba, in the northern
Yucatan Peninsula, and elsewhere along the northern U.S. Gulf coast
should monitor the progress of this system.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area
outside of the United States, please monitor products issued by
your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 1100 PM EDT (0300 UTC), the center of Tropical Storm Ida was
located near latitude 18.6 North, longitude 80.5 West. Ida is moving
toward the northwest near 12 mph (26 km/h) and this general
motion should continue over the next few days. On the forecast
track, the center of Ida will pass near or over the Cayman Islands
during the next few hours, the Isle of Youth and western Cuba
Friday, and over the southeastern and central Gulf of Mexico Friday
night and Saturday. The system is forecast to approach the U.S.
northern Gulf coast on Sunday.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Ida is forecast to become a hurricane over the southeastern Gulf of
Mexico in a day or two with additional strengthening expected
thereafter. Ida could be near major hurricane strength when it
approaches the northern Gulf coast.

Tropical-storm-force winds extend outward up to 70 miles (110 km)
from the center.

The estimated minimum central pressure is 1006 mb (29.71 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Storm Ida can be found in the
Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO
header WTNT44 KNHC, and on the web at
hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 2 to 4 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...

Morgan City, LA to Ocean Springs, MS including Lake Borgne...7-11 ft
Rockefeller Wildlife Refuge, LA to Morgan City, LA including
Vermilion Bay...4-7 ft
Ocean Springs, MS to MS/AL border...4-7 ft
MS/AL border to AL/FL border including Mobile Bay...3-5 ft
Lake Pontchartrain...3-5 ft
Lake Maurepas...2-4 ft
Sabine Pass to Rockefeller Wildlife Refuge, LA...2-4 ft

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Tropical storm conditions are expected in the Cayman Islands
tonight, and are expected to reach the Isle of Youth and portions of
western Cuba in the warning area on Friday. Hurricane conditions
are possible in the hurricane watch area along the northern Gulf
coast late Saturday night or Sunday and tropical storm conditions
are possible in the watch area late Saturday night or Sunday.

RAINFALL: Tropical Storm Ida is expected to produce total rainfall
accumulations of 6 to 10 inches with maximum totals of 15 inches
across Jamaica. Rainfall totals of 8 to 12 inches with isolated
maximum amounts of 20 inches are expected across the Cayman Islands
and western Cuba, including the Isle of Youth. These rainfall
amounts may produce life-threatening flash floods and mudslides.

Tropical Storm Ida is likely to bring rainfall amounts of 8 to 12
inches with isolated maximum amounts up to 15 inches along the
central Gulf Coast Sunday into Monday. This is likely to result in
flash, urban, small stream, and riverine flooding to the central
Gulf Coast.

SURF: Swells generated by this system will affect Jamaica, the
Cayman Islands and Cuba tonight and Friday. Swells will begin
reaching portions of the northern Gulf coast Saturday night or
early Sunday. These swells are likely to cause life-threatening
surf and rip current conditions. Please consult products from your
local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 200 AM EDT.
Next complete advisory at 500 AM EDT.

$$
Forecaster Cangialosi



Tropical Storm Ida Discussion Number 3
NWS National Hurricane Center Miami FL AL092021
1100 PM EDT Thu Aug 26 2021

The Air Force Hurricane Hunters have been investigating Ida this
evening and found maximum flight-level winds of 47 kt at 2500 ft.
This data along with numerous unflagged 35-kt SFMR winds supported
raising the intensity to 35 kt earlier this evening. Since the
aircraft departed Ida, there has been generally little change in the
storm's structure, so the initial intensity is held at 35 kt. Ida
is an asymmetric tropical storm with most of the deep convection and
stronger winds confined to the eastern half of the circulation.
Both the NOAA and Air Force Hurricane Hunters will be investigating
Ida Friday morning.

The storm has been wobbling around, but smoothing through the recent
erratic motion yields an initial motion estimate of 320/10 kt. A
mid-level ridge centered off the southeast U.S. coast is expected to
shift westward on Friday and over the weekend. This feature should
keep Ida moving in a general northwestward motion for the next 2 or
3 days, taking the core of the system over western Cuba Friday
afternoon or evening and then across the southern and central Gulf
of Mexico this weekend. Although there is some timing differences
in the models, they are in fairly good agreement that Ida will make
landfall in Louisiana late Sunday or early Monday. The GFS and ECMWF
ensemble members basically span a similar region and are most
concentrated across the state of Louisiana. Users are reminded to
not focus on the exact forecast track as impacts will extend far
from the center and the average 72-hour track error is around 120
miles.

There is some southwesterly vertical wind shear affecting Ida at the
moment, which is the likely part of the reason the cloud pattern and
wind field are asymmetric. However, the global model show the
upper-level pattern becoming quite favorable late Friday and through
the weekend. These more conducive winds aloft combined with very
warm SSTs and abundant moisture is likely to result in steady or
rapid intensification until Ida makes landfall in the U.S. The
intensity guidance unanimously show Ida becoming a hurricane, but
there is notable spread in how strong the system will become. Given
the expected favorable environmental conditions for the storm, the
NHC intensity forecast lies near the high end of the model guidance,
in best agreement with the regional hurricane models. It is also
worth noting that even though the global models are not particularly
accurate in predicting tropical cyclone winds, the GFS and ECMWF
show the minimum pressure falling more than 35 mb from the current
conditions. Based on all of this information, there is
higher-than-normal confidence that a significant hurricane will be
approaching the Gulf coast late in the weekend.

Key Messages:

1. Tropical storm conditions are expected in portions of the Cayman
Islands tonight and in portions of western Cuba and the Isle of
Youth Friday, where a dangerous storm surge is also possible in
areas of onshore flow. Life-threatening heavy rains, flash flooding
and mudslides are expected across Jamaica, the Cayman Islands, and
western Cuba, including the Isle of Youth.

2. There is an increasing risk of life-threatening storm surge
inundation along the coasts of Louisiana, Mississippi, and Alabama,
where a Storm Surge Watch is in effect. Interests in these areas
should follow any advice given by local officials.

3. There is an increasing risk of dangerous hurricane-force winds
beginning Sunday along the portions of the coasts of Louisiana and
Mississippi, including metropolitan New Orleans, where a Hurricane
Watch is in effect.

4. Ida is likely to produce heavy rainfall Sunday into Monday along
the central Gulf coast resulting in flash, urban, small stream, and
riverine flooding. Heavy rainfall and flooding impacts are likely
along the central Gulf Coast Sunday into Monday.


FORECAST POSITIONS AND MAX WINDS

INIT 27/0300Z 18.6N 80.5W 35 KT 40 MPH
12H 27/1200Z 19.9N 82.0W 45 KT 50 MPH
24H 28/0000Z 21.8N 83.9W 55 KT 65 MPH...NEAR CUBA
36H 28/1200Z 23.8N 85.9W 65 KT 75 MPH
48H 29/0000Z 25.6N 88.0W 75 KT 85 MPH
60H 29/1200Z 27.3N 89.6W 85 KT 100 MPH
72H 30/0000Z 29.0N 90.6W 95 KT 110 MPH...NEAR THE COAST
96H 31/0000Z 32.0N 91.0W 45 KT 50 MPH...INLAND
120H 01/0000Z 33.9N 88.8W 25 KT 30 MPH...INLAND

$$
Forecaster Cangialosi

[cycloneye]

BULLETIN
Tropical Storm Ida Advisory Number 4
NWS National Hurricane Center Miami FL AL092021
500 AM EDT Fri Aug 27 2021

...IDA STRENGTHENS AS THE CENTER PASSES THROUGH THE CAYMAN
ISLANDS...
...AIR FORCE RESERVE AND NOAA HURRICANE HUNTER AIRCRAFT ENROUTE TO
INVESTIGATE THE STORM...


SUMMARY OF 500 AM EDT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...20.0N 81.4W
ABOUT 50 MI...80 KM NNW OF GRAND CAYMAN
ABOUT 145 MI...230 KM SE OF THE ISLE OF YOUTH
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...1001 MB...29.56 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Watch is in effect for...
* Sabine Pass to Alabama/Florida border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, Lake Maurepas, and
Mobile Bay

A Hurricane Watch is in effect for...
* Cameron, Louisiana to the Mississippi/Alabama border
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Tropical Storm Warning is in effect for...
* Cayman Islands
* Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.
For a depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere in central and western Cuba, in the northern
Yucatan Peninsula, and elsewhere along the northern U.S. Gulf coast
should monitor the progress of this system. Hurricane warnings
will likely be required for portions of the northern Gulf coast
later today. Interests in the Dry Tortugas should also monitor the
progress of Ida.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area
outside of the United States, please monitor products issued by
your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 500 AM EDT (0900 UTC), the center of Tropical Storm Ida was
located by weather radar on Grand Cayman near latitude 20.0 North,
longitude 81.4 West. Ida is moving toward the northwest near 15 mph
(24 km/h) and this general motion should continue over the
next few days. On the forecast track, the center of Ida will
move away from the Cayman Islands this morning, pass near or over
the Isle of Youth and western Cuba later today, and over the
southeastern and central Gulf of Mexico tonight and Saturday.
The system is forecast to approach the U.S. northern Gulf coast on
Sunday.

Maximum sustained winds have increased to near 45 mph (75 km/h)
with higher gusts, and additional steady to rapid strengthening is
expected during the next few days. Ida is forecast to become a
hurricane over the southeastern Gulf of Mexico in a day or two,
and to be at or near major hurricane strength when it approaches
the northern Gulf coast.

Tropical-storm-force winds extend outward up to 80 miles (130 km)
from the center.

The estimated minimum central pressure is 1001 mb (29.56 inches).
Grand Cayman Island recently reported a pressure of 1003 mb (29.62
inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Storm Ida can be found in the
Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO
header WTNT44 KNHC, and on the web at
hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 2 to 4 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...

Morgan City, LA to Ocean Springs, MS including Lake Borgne...7-11 ft
Rockefeller Wildlife Refuge, LA to Morgan City, LA including
Vermilion Bay...4-7 ft
Ocean Springs, MS to MS/AL border...4-7 ft
MS/AL border to AL/FL border including Mobile Bay...3-5 ft
Lake Pontchartrain...3-5 ft
Lake Maurepas...2-4 ft
Sabine Pass to Rockefeller Wildlife Refuge, LA...2-4 ft

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Tropical storm conditions are expected in the Cayman Islands
this morning, and are expected to reach the Isle of Youth and
portions of western Cuba in the warning area later today. Hurricane
conditions are possible in the hurricane watch area along the
northern Gulf coast late Saturday night or Sunday and tropical storm
conditions are possible in the watch area late Saturday night or
Sunday.

RAINFALL: Ida is expected to produce total rainfall accumulations
of 6 to 10 inches with maximum totals of 15 inches across Jamaica.
Rainfall totals of 8 to 12 inches with isolated maximum amounts of
20 inches are expected across the Cayman Islands and western Cuba,
including the Isle of Youth. These rainfall amounts may produce
life-threatening flash floods and mudslides.

As Ida approaches the central Gulf Coast Sunday afternoon, total
rainfall accumulations of 8 to 16 inches with isolated maximum
amounts of 20 inches are possible from southeast Louisiana to
coastal Mississippi and Alabama through Monday morning. Ida is
forecast to turn northeast as it moves inland later Monday with
rainfall totals of 4 to 8 inches possible across southern and
central Mississippi. This is likely to result in considerable flash,
urban, small stream, and riverine flooding.

SURF: Swells generated by this system will affect Jamaica, the
Cayman Islands and Cuba tonight and Friday. Swells will begin
reaching portions of the northern Gulf coast Saturday night or
early Sunday. These swells are likely to cause life-threatening
surf and rip current conditions. Please consult products from your
local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 800 AM EDT.
Next complete advisory at 1100 AM EDT.

$$
Forecaster Beven


Tropical Storm Ida Discussion Number 4
NWS National Hurricane Center Miami FL AL092021
500 AM EDT Fri Aug 27 2021

Radar data from Grand Cayman and satellite imagery indicate that Ida
is becoming better organized just to the north of Grand Cayman. The
convection has become more concentrated near the center, and the
radar data is showing increasing curved banding. In addition, the
pressure at Grand Cayman fell to 1003 mb, showing that the central
pressure is lower than observed by the aircraft mission yesterday
afternoon. Based on a combination of the Grand Cayman observations
and satellite intensity estimates from TAFB and SAB, the initial
intensity is increased to 40 kt. Air Force Reserve and NOAA
Hurricane Hunter aircraft are scheduled to investigate Ida near 12Z.

After the earlier wobbling, Ida seems to have resumed a
northwestward motion of 320/13. A mid-level ridge centered off the
southeast U.S. coast is expected to shift westward through the
weekend. This feature should keep Ida moving on a general
northwestward track for the next 2 or 3 days, taking the core of
the system over western Cuba this afternoon or evening and then
across the southern and central Gulf of Mexico this weekend.
Although some model timing differences remain, they are in fairly
good agreement that Ida will make landfall in Louisiana late Sunday
or early Monday. The new forecast track is shifted a little to the
east of the previous forecast through 48 h based on the initial
location. However, the 60 and 72 h positions are similar to the
previous forecast, and thus there is no significant change to the
forecast landfall area in Louisiana at this time. Users are
reminded to not focus on the exact forecast track as impacts will
extend far from the center and the average 72-hour track error is
around 120 miles.

There continues to be some southwesterly shear affecting Ida due to
the storm's location between an upper-level trough to the west and
an upper-level anticyclone to the east. Some decrease in the shear
is expected during the next 24 h, and that, combined with a moist
environment and warm sea surface temperatures along the forecast
track, should allow steady to rapid strengthening until the cyclone
makes landfall along the northern Gulf coast. The new intensity
forecast is slightly stronger than the previous forecast, and it now
calls for Ida to reach a peak intensity of 100 kt before landfall.
It should be noted that this intensity is lower than that forecast
by the HMON model, the HCCA corrected consensus model, and the
Florida State Superensemble. After landfall, Ida should weaken as
it moves through the lower Mississippi and Tennessee River valleys.
Based on the available guidance, there remains higher-than-normal
confidence that a significant hurricane will approach and impact the
Gulf coast during the weekend and early next week.


Key Messages:

1. Tropical storm conditions are occurring in portions of the Cayman
Islands, and they are expected in portions of western Cuba and the
Isle of Youth today, where a dangerous storm surge is also possible
in areas of onshore flow. Life-threatening heavy rains, flash
flooding and mudslides are expected across Jamaica, the Cayman
Islands, and western Cuba, including the Isle of Youth.

2. There is an increasing risk of life-threatening storm surge
inundation along the coasts of Louisiana, Mississippi, and Alabama,
where a Storm Surge Watch is in effect. Interests in these areas
should follow any advice given by local officials.

3. There is an increasing risk of dangerous hurricane-force winds
beginning Sunday along the portions of the coasts of Louisiana and
Mississippi, including metropolitan New Orleans, where a Hurricane
Watch is in effect.

4. Ida is also expected to produce heavy rains across the central
Gulf Coast from southeast Louisiana to coastal Mississippi, Alabama,
as well as the Lower Mississippi Valley starting Sunday into Monday,
resulting in considerable flash, urban, small stream, and riverine
flooding.


FORECAST POSITIONS AND MAX WINDS

INIT 27/0900Z 20.0N 81.4W 40 KT 45 MPH
12H 27/1800Z 21.5N 82.9W 50 KT 60 MPH...OVER ISLE OF YOUTH
24H 28/0600Z 23.4N 84.9W 60 KT 70 MPH
36H 28/1800Z 25.3N 86.9W 70 KT 80 MPH
48H 29/0600Z 27.1N 88.8W 85 KT 100 MPH
60H 29/1800Z 28.7N 90.2W 100 KT 115 MPH
72H 30/0600Z 30.1N 91.1W 85 KT 100 MPH...INLAND
96H 31/0600Z 33.0N 90.5W 35 KT 40 MPH...INLAND
120H 01/0600Z 35.0N 88.0W 25 KT 30 MPH...INLAND

$$
Forecaster Beven

[cycloneye]

BULLETIN
Tropical Storm Ida Intermediate Advisory Number 4A
NWS National Hurricane Center Miami FL AL092021
800 AM EDT Fri Aug 27 2021

...AIR FORCE AND NOAA AIRCRAFT FIND IDA STRENGTHENING OVER THE
NORTHWEST CARIBBEAN SEA...


SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...20.3N 81.7W
ABOUT 75 MI...125 KM NNW OF GRAND CAYMAN
ABOUT 115 MI...185 KM SE OF THE ISLE OF YOUTH
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...996 MB...29.41 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of the Cayman Islands has discontinued the Tropical
Storm Warning for Grand Cayman. The Tropical Storm Warning remains
in effect for Little Cayman and Cayman Brac.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Watch is in effect for...
* Sabine Pass to Alabama/Florida border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, Lake Maurepas, and
Mobile Bay

A Hurricane Watch is in effect for...
* Cameron, Louisiana to the Mississippi/Alabama border
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Tropical Storm Warning is in effect for...
* Little Cayman and Cayman Brac
* Cuban provinces of Matanzas, Mayabeque, Havana, Artemisa, Pinar
del Rio, and the Isle of Youth

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.
For a depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere in central and western Cuba and elsewhere along
the northern U.S. Gulf coast should monitor the progress of this
system. Hurricane warnings will likely be required for portions of
the northern Gulf coast later today. Interests in the Dry Tortugas
should also monitor the progress of Ida.

For storm information specific to your area in the United States,
including possible inland watches and warnings, please monitor
products issued by your local National Weather Service forecast
office. For storm information specific to your area outside of the
United States, please monitor products issued by your national
meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 800 AM EDT (1200 UTC), the center of Tropical Storm Ida was
located by reconnaissance aircraft and weather radar on Grand
Cayman near latitude 20.3 North, longitude 81.7 West. Ida is moving
toward the northwest near 15 mph (24 km/h) and this general motion
should continue over the next few days. On the forecast track, the
center of Ida will move away from the Cayman Islands this morning,
pass near or over the Isle of Youth and western Cuba later today,
and move over the southeastern and central Gulf of Mexico tonight
and Saturday. The system is forecast to approach the U.S. northern
Gulf coast on Sunday.

Data from Air Force Reserve and NOAA reconnaissance aircraft
indicate that the maximum sustained winds have increased to near 60
mph (95 km/h) with higher gusts, and additional steady to rapid
strengthening is expected during the next few days. Ida is forecast
to become a hurricane over the southeastern Gulf of Mexico, and to
be at or near major hurricane strength when it approaches the
northern Gulf coast.

Tropical-storm-force winds extend outward up to 80 miles (130 km)
from the center.

The estimated minimum central pressure from reconnaissance
aircraft data is 996 mb (29.41 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Storm Ida can be found in the
Tropical Cyclone Discussion under AWIPS header MIATCDAT4, WMO
header WTNT44 KNHC, and on the web at
hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 2 to 4 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...

Morgan City, LA to Ocean Springs, MS including Lake Borgne...7-11 ft
Rockefeller Wildlife Refuge, LA to Morgan City, LA including
Vermilion Bay...4-7 ft
Ocean Springs, MS to MS/AL border...4-7 ft
MS/AL border to AL/FL border including Mobile Bay...3-5 ft
Lake Pontchartrain...4-6 ft
Lake Maurepas...3-5 ft
Sabine Pass to Rockefeller Wildlife Refuge, LA...2-4 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Tropical storm conditions are expected on Little Cayman
and Cayman Brac this morning, and are expected to reach the Isle of
Youth and portions of western Cuba in the warning area later today.
Hurricane conditions are possible in the hurricane watch area along
the northern Gulf coast late Saturday night or Sunday and tropical
storm conditions are possible in the watch area late Saturday night
or Sunday.

RAINFALL: Ida is expected to produce total rainfall accumulations
of 6 to 10 inches with maximum totals of 15 inches across Jamaica.
Rainfall totals of 8 to 12 inches with isolated maximum amounts of
20 inches are expected across the Cayman Islands and western Cuba,
including the Isle of Youth. These rainfall amounts may produce
life-threatening flash floods and mudslides.

As Ida approaches the central Gulf Coast Sunday afternoon, total
rainfall accumulations of 8 to 16 inches with isolated maximum
amounts of 20 inches are possible from southeast Louisiana to
coastal Mississippi and Alabama through Monday morning. Ida is
forecast to turn northeast as it moves inland later Monday with
rainfall totals of 4 to 8 inches possible across southern and
central Mississippi. This is likely to result in considerable flash,
urban, small stream, and riverine flooding.

SURF: Swells generated by this system will affect Jamaica, the
Cayman Islands and Cuba tonight and Friday. Swells will begin
reaching portions of the northern Gulf coast Saturday night or
early Sunday. These swells are likely to cause life-threatening
surf and rip current conditions. Please consult products from your
local weather office.


NEXT ADVISORY
-------------
Next complete advisory at 1100 AM EDT.

$$
Forecaster Brown

[cycloneye]

BULLETIN
Tropical Storm Ida Advisory Number 5
NWS National Hurricane Center Miami FL AL092021
1100 AM EDT Fri Aug 27 2021

...IDA CONTINUES TO STRENGTHEN...
...HURRICANE WARNING ISSUED FOR THE ISLE OF YOUTH AND WESTERN
CUBA...


SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...20.7N 82.1W
ABOUT 75 MI...125 KM SE OF THE ISLE OF YOUTH
ABOUT 200 MI...320 KM ESE OF THE WESTERN TIP OF CUBA
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...996 MB...29.42 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of Cuba has replace the Tropical Storm Warning with
a Hurricane Warning for the Isle of Youth, and the Cuban provinces
of Pinar del Rio and Artemisa.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Warning is in effect for...
* Cuban provinces of Pinar del Rio and Artemisa, and the Isle of
Youth

A Storm Surge Watch is in effect for...
* Sabine Pass to Alabama/Florida border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, Lake Maurepas, and
Mobile Bay

A Hurricane Watch is in effect for...
* Cameron, Louisiana to the Mississippi/Alabama border
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Tropical Storm Warning is in effect for...
* Little Cayman and Cayman Brac
* Cuban provinces of Matanzas, Mayabeque, and Havana

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area, in this case within the next 12
hours.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.
For a depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere in central and western Cuba and elsewhere along
the northern U.S. Gulf coast should monitor the progress of this
system. Hurricane warnings will likely be required for portions of
the northern Gulf coast later today. Interests in the Dry Tortugas
should also monitor the progress of Ida.

For storm information specific to your area in the United States,
including possible inland watches and warnings, please monitor
products issued by your local National Weather Service forecast
office. For storm information specific to your area outside of the
United States, please monitor products issued by your national
meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 1100 AM EDT (1500 UTC), the center of Tropical Storm Ida was
located near latitude 20.7 North, longitude 82.1 West. Ida is moving
toward the northwest near 15 mph (24 km/h), and this general motion
should continue over the next few days. On the forecast track, the
center of Ida will pass near or over the Isle of Youth and western
Cuba later today, and move over the southeastern and central Gulf
of Mexico tonight and Saturday. Ida is forecast to make landfall
along the U.S. northern Gulf coast within the hurricane watch area
on Sunday.

Reports from Air Force and NOAA reconnaissance aircraft indicate
that the maximum sustained winds have increased to near 65 mph
(100 km/h) with higher gusts. Additional strengthening is forecast
today and Ida is expected to be a hurricane when it nears western
Cuba later today. Steady to rapid strengthening is expected when
Ida moves over the southeastern and central Gulf of Mexico over the
weekend, and Ida is expected to be a major hurricane when it
approaches the northern Gulf coast.

Tropical-storm-force winds extend outward up to 90 miles (150 km)
from the center. A wind gust to 45 mph (72 km/h) was recently
reported on Cayman Brac and a wind gust to 41 mph (67 km/h) has
been observed on Cayo Largo, Cuba, within the past hour or two.

The latest minimum central pressure reported by an Air Force
Reserve reconnaissance aircraft is 996 mb (29.42 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 4 to 6 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...

Morgan City, LA to Ocean Springs, MS including Lake Borgne...7-11 ft
Rockefeller Wildlife Refuge, LA to Morgan City, LA including
Vermilion Bay...4-7 ft
Ocean Springs, MS to MS/AL border...4-7 ft
MS/AL border to AL/FL border including Mobile Bay...3-5 ft
Lake Pontchartrain...4-6 ft
Lake Maurepas...3-5 ft
Sabine Pass to Rockefeller Wildlife Refuge, LA...2-4 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Tropical storm conditions are expected on Little Cayman
and Cayman Brac through early this afternoon. Hurricane conditions
are expected to reach the Isle of Youth and portions of western Cuba
in the Hurricane Warning area by later this afternoon and evening,
with tropical storm conditions beginning within the next couple of
hours on the Isle of Youth.

Hurricane conditions are possible in the hurricane watch area along
the northern Gulf coast late Saturday night or Sunday and tropical
storm conditions are possible in the watch area late Saturday night
or Sunday.

RAINFALL: Ida is expected to produce total rainfall accumulations
of 6 to 10 inches with maximum totals of 15 inches across Jamaica.
Rainfall totals of 8 to 12 inches with isolated maximum amounts of
20 inches are expected across the Cayman Islands and western Cuba,
including the Isle of Youth. These rainfall amounts may produce
life-threatening flash floods and mudslides.

As Ida approaches the central Gulf Coast Sunday afternoon, total
rainfall accumulations of 8 to 16 inches with isolated maximum
amounts of 20 inches are possible from southeast Louisiana to
coastal Mississippi and Alabama through Monday morning. Ida is
forecast to turn northeast as it moves inland later Monday with
rainfall totals of 4 to 8 inches possible across southern and
central Mississippi. This is likely to result in considerable flash,
urban, small stream, and riverine flooding.

SURF: Swells generated by this system will affect the Cayman
Islands and Cuba through tonight. Swells will begin reaching
portions of the northern Gulf coast Saturday night or early Sunday.
These swells are likely to cause life-threatening surf and rip
current conditions. Please consult products from your local weather
office.


NEXT ADVISORY
-------------
Next intermediate advisory at 200 PM EDT.
Next complete advisory at 500 PM EDT.

$$
Forecaster Brown




Tropical Storm Ida Discussion Number 5
NWS National Hurricane Center Miami FL AL092021
1100 AM EDT Fri Aug 27 2021

Radar imagery from Grand Cayman and Cuba as well as satellite data
continue to show an improvement in Ida's overall structure this
morning, with an increase in banding, the development of a small
central dense overcast, and more recently an improved inner-core
feature. Both the NOAA and Air Force reconnaissance aircraft
reported that the pressure has fallen to around 996 mb, and the Air
Force plane has measured flight-level and SFMR winds that support
an initial intensity of 55 kt.

Although there is still some southwesterly shear over Ida, the
outflow has begun to expand over the northeastern and southeastern
portions of the circulation. The upper-level trough near the
Yucatan peninsula that has been imparting the shear over Ida is
forecast to weaken and move westward during the next 12 to 24
hours, which should result in a more favorable upper-level
wind pattern. This, in combination with warm sea surface
temperatures and a moist environment along the forecast track of
the storm are expected to result in steady to rapid strengthening.
Ida is now foreast to become a hurricane when it is near western
Cuba and once it moves over the southeastern Gulf of Mexico a period
of rapid strengthening is likely to begin, with the NHC intensity
forecast explicitly calling for rapid intensification to major
hurricane strength between 24 and 48 hours. The official intensity
forecast is on the higher side of the intensity guidance but not
quite as high as the slightly more aggressive CTCI, HWRF, and HCCA
models. In addition to the increase in strength, the dynamical
model guidance indicates that Ida's wind field will grow larger as
it moves over the Gulf of Mexico and this is reflected in the NHC
wind radii forecast. In summary, there is a higher-than-normal
confidence that a significant hurricane will impact a large portion
of the northern Gulf coast by late this weekend and early next week.

Ida is moving northwestward or 320/13 kt. The track forecast
reasoning is unchanged from before. A mid-level ridge over the
western Atlantic is forecast to move westward and this should keep
Ida on a general northwestward heading during the next 48-60 hours.
This track will bring the storm across western Cuba later today,
over the southeastern and central Gulf of Mexico on Saturday and
Saturday night, to the coast of Louisiana by late Sunday. The
track guidance is in remarkably good agreement with very little
cross-track spread during the first 60 hours or so of the forecast
period. After that time, Ida is forecast to reach the western
portion of the ridge, which is expected to cause the storm to slow
down and turn northward and then northeastward over the
southeastern United States. The NHC track forecast is near or
just east of the various consensus aids, in best agreement with the
GFS ensemble mean. Although the small spread in the guidance
through landfall increases the overall confidence in the track
forecast, users are reminded to not focus on the exact details of
the forecast track as storm surge, wind, and rainfall impacts will
extend far from the center.

Key Messages:

1. Life-threatening storm surge and hurricane conditions are
expected later today and tonight in portions of western Cuba,
including the Isle of Youth, where a Hurricane Warning is in effect.
Life-threatening heavy rains, flash flooding and mudslides are
expected across Jamaica, the Cayman Islands, and western Cuba,
including the Isle of Youth.

2. The risk of life-threatening storm surge inundation is increasing
along the coasts of Louisiana, Mississippi, and Alabama. Inundation
of 7 to 11 feet above ground level is possible within the area from
Morgan City, Louisiana, to Ocean Springs, Mississippi, including
Lake Borgne. Interests in these areas should follow any advice given
by local officials.

3. Ida is expected to be a dangerous major hurricane when it reaches
the northern Gulf Coast on Sunday, and the risk of hurricane-force
winds continues to increase, especially along portions of the
Louisiana coast, including metropolitan New Orleans. Potentially
devastating wind damage could occur where the core of Ida moves
onshore.

4. Ida is likely to produce heavy rainfall later Sunday into Monday
across the central Gulf Coast from southeast Louisiana to coastal
Mississippi and Alabama, as well as the Lower Mississippi Valley,
resulting in considerable flash, urban, small stream, and riverine
flooding.

FORECAST POSITIONS AND MAX WINDS

INIT 27/1500Z 20.7N 82.1W 55 KT 65 MPH
12H 28/0000Z 22.2N 83.7W 65 KT 75 MPH...OVER WESTERN CUBA
24H 28/1200Z 24.0N 85.8W 75 KT 85 MPH...OVER WATER
36H 29/0000Z 25.9N 87.8W 90 KT 105 MPH
48H 29/1200Z 27.6N 89.7W 105 KT 120 MPH
60H 30/0000Z 29.0N 90.8W 105 KT 120 MPH
72H 30/1200Z 30.3N 91.3W 60 KT 70 MPH...INLAND
96H 31/1200Z 33.3N 90.2W 30 KT 35 MPH...INLAND
120H 01/1200Z 35.2N 87.1W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Brown

[AlphaToOmega]

000
WTNT64 KNHC 271712
TCUAT4

Hurricane Ida Tropical Cyclone Update
NWS National Hurricane Center Miami FL AL092021
115 PM EDT Fri Aug 27 2021

...IDA STRENGTHENS INTO A HURRICANE AS IT NEARS THE ISLE OF YOUTH...

Data from an Air Force Reserve hurricane hunter aircraft indicate
that Ida has strengthened into a hurricane as it approaches the
Isle of Youth, Cuba. The maximum sustained winds are estimated to
be 75 mph (120 km/h) with higher gusts.

A sustained wind of 44 mph (70 km/h) and a gust of 60 mph (96 km/h)
were recently reported on Cayo Largo, Cuba.


SUMMARY OF 110 PM EDT...1710 UTC...INFORMATION
----------------------------------------------
LOCATION...21.4N 82.4W
ABOUT 30 MI...50 KM ESE OF THE ISLE OF YOUTH
ABOUT 165 MI...270 KM E OF THE WESTERN TIP OF CUBA
MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...987 MB...29.15 INCHES

$$
Forecaster Brown

[cycloneye]

BULLETIN
Hurricane Ida Intermediate Advisory Number 5A
NWS National Hurricane Center Miami FL AL092021
200 PM EDT Fri Aug 27 2021

...IDA MAKES LANDFALL AS A HURRICANE ON THE ISLE OF YOUTH...


SUMMARY OF 200 PM EDT...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...21.6N 82.7W
ABOUT 5 MI...10 KM E OF THE CENTER OF THE ISLE OF YOUTH
ABOUT 145 MI...245 KM E OF THE WESTERN TIP OF CUBA
MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...987 MB...29.15 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The government of the Cayman Islands has discontinued all Tropical
Storm Warnings.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Warning is in effect for...
* Cuban provinces of Pinar del Rio and Artemisa, and the Isle of
Youth

A Storm Surge Watch is in effect for...
* Sabine Pass to Alabama/Florida border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, Lake Maurepas, and
Mobile Bay

A Hurricane Watch is in effect for...
* Cameron, Louisiana to the Mississippi/Alabama border
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Tropical Storm Warning is in effect for...
* Cuban provinces of Matanzas, Mayabeque, and Havana

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.
For a depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere in central and western Cuba and elsewhere along
the northern U.S. Gulf coast should monitor the progress of this
system. Hurricane warnings will likely be required for portions of
the northern Gulf coast later today. Interests in the Dry Tortugas
should also monitor the progress of Ida.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area
outside of the United States, please monitor products issued by
your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 200 PM EDT (1800 UTC), the center of Hurricane Ida was located
by Cuban radar and Air Force Reserve Hurricane Hunter aircraft near
latitude 21.6 North, longitude 82.7 West. Ida is moving toward the
northwest near 15 mph (24 km/h), and this general motion should
continue over the next few days. On the forecast track, the
center of Ida will pass over the Isle of Youth during the next
hour or so, move over western Cuba later today, and move over the
southeastern and central Gulf of Mexico tonight and Saturday. Ida
is forecast to make landfall along the U.S. northern Gulf coast
within the hurricane watch area on Sunday.

Reports from Air Force Reserve reconnaissance aircraft indicate
that the maximum sustained winds are near 75 mph (120 km/h) with
higher gusts. Additional strengthening is forecast before the
center moves over western Cuba later today. Steady to rapid
strengthening is expected when Ida moves over the southeastern and
central Gulf of Mexico over the weekend, and Ida is expected to be
a major hurricane when it approaches the northern Gulf coast.

Hurricane-force winds extend outward up to 20 miles (30 km) from the
center. Tropical-storm-force winds extend outward up to 90 miles
(150 km) from the center. Sustained winds of 38 mph (61 km/h) and a
gust to 55 mph (89 km/h) has recently been observed on Cayo Largo,
Cuba.

The latest minimum central pressure estimated from Air Force
Reserve reconnaissance aircraft data is 987 mb (29.15 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 4 to 6 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...

Morgan City, LA to Ocean Springs, MS including Lake Borgne...7-11 ft
Rockefeller Wildlife Refuge, LA to Morgan City, LA including
Vermilion Bay...4-7 ft
Ocean Springs, MS to MS/AL border...4-7 ft
MS/AL border to AL/FL border including Mobile Bay...3-5 ft
Lake Pontchartrain...4-6 ft
Lake Maurepas...3-5 ft
Sabine Pass to Rockefeller Wildlife Refuge, LA...2-4 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Hurricane conditions are occuring over the Isle of Youth
and are expected to spread over portions of western Cuba in the
hurricane warning area by later this afternoon and evening.
Tropical storm conditions are already beginning to reach portions
of western Cuba and will continue through early Saturday.

Hurricane conditions are possible in the hurricane watch area along
the northern Gulf coast late Saturday night or Sunday and tropical
storm conditions are possible in the watch area late Saturday night
or Sunday.

RAINFALL: Ida is expected to produce total rainfall accumulations
of 6 to 10 inches with maximum totals of 15 inches across Jamaica.
Rainfall totals of 8 to 12 inches with isolated maximum amounts of
20 inches are expected across the Cayman Islands and western Cuba,
including the Isle of Youth. These rainfall amounts may produce
life-threatening flash floods and mudslides.

As Ida approaches the central Gulf Coast Sunday afternoon, total
rainfall accumulations of 8 to 16 inches with isolated maximum
amounts of 20 inches are possible from southeast Louisiana to
coastal Mississippi and Alabama through Monday morning. Ida is
forecast to turn northeast as it moves inland later Monday with
rainfall totals of 4 to 8 inches possible across southern and
central Mississippi. This is likely to result in considerable flash,
urban, small stream, and riverine flooding.

SURF: Swells generated by this system will affect the Cayman
Islands and Cuba through tonight. Swells will begin reaching
portions of the northern Gulf coast Saturday night or early Sunday.
These swells are likely to cause life-threatening surf and rip
current conditions. Please consult products from your local weather
office.


NEXT ADVISORY
-------------
Next complete advisory at 500 PM EDT.

$$
Forecaster Brown

[cycloneye]

BULLETIN
Hurricane Ida Advisory Number 6
NWS National Hurricane Center Miami FL AL092021
500 PM EDT Fri Aug 27 2021

...CENTER OF IDA APPROACHING WESTERN CUBA...
...STORM SURGE AND HURRICANE WARNINGS ISSUES FOR PORTIONS OF THE
NORTHERN GULF COAST...


SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...22.1N 83.2W
ABOUT 45 MI...70 KM NW OF THE ISLE OF YOUTH
ABOUT 90 MI...145 KM SW OF HAVANA CUBA
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...985 MB...29.09 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

A Storm Surge Warning has been issued from east of Rockefeller
Wildlife Refuge, Louisiana, to the Mississippi/Alabama border
including Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake
Maurepas.

A Hurricane Warning has been issued for the coast of Louisiana from
Intracoastal City to the Mouth of the Pearl River, including Lake
Pontchartrain, Lake Maurepas, and Metropolitan New Orleans.

A Tropical Storm Warning has been issued for the northern Gulf
coast from the Mouth of the Pearl River to the Mississippi/Alabama
border. A Tropical Storm Warning has also been issued for the coast
of Louisiana from west of Intracoastal City to Cameron.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* East of Rockefeller Wildlife Refuge Louisiana to the
Mississippi/Alabama border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas

A Hurricane Warning is in effect for...
* Cuban provinces of Pinar del Rio and Artemisa, and the Isle of
Youth
* Intracoastal City Louisiana to the Mouth of the Pearl River
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Storm Surge Watch is in effect for...
* Sabine Pass to Rockefeller Wildlife Refuge Louisiana
* Mobile Bay

A Hurricane Watch is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Warning is in effect for...
* Cuban provinces of Matanzas, Mayabeque, and Havana
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov. This is a life-threatening situation. Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions. Promptly follow evacuation and other
instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of
tropical-storm-force winds, conditions that make outside
preparations difficult or dangerous. Preparations to protect life
and property should be rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere along the northern U.S. Gulf coast should
monitor the progress of this system. Interests in the Dry Tortugas
should also monitor the progress of Ida.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area
outside of the United States, please monitor products issued by
your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 500 PM EDT (2100 UTC), the center of Hurricane Ida was located
near latitude 22.1 North, longitude 83.2 West. Ida is moving toward
the northwest near 15 mph (24 km/h), and this general motion should
continue until Ida reaches the northern Gulf coast on Sunday. A
slower northward motion is forecast after Ida reaches the northern
Gulf coast. On the forecast track, the center of Ida will pass
over western Cuba during the next several hours, and then move over
the southeastern and central Gulf of Mexico later tonight and
Saturday. Ida is forecast to make landfall along the U.S. northern
Gulf coast within the hurricane warning area on Sunday.

Maximum sustained winds have increased to near 80 mph (130 km/h)
with higher gusts. Little change in strength is anticipated while
Ida moves over western Cuba this evening. Steady to rapid
strengthening is expected when Ida moves over the southeastern and
central Gulf of Mexico over the weekend, and Ida is expected to be
an extremely dangerous major hurricane when it approaches the
northern Gulf coast on Sunday.

Hurricane-force winds extend outward up to 25 miles (35 km) from the
center and tropical-storm-force winds extend outward up to 90 miles
(150 km). A wind gust to 46 mph (74 km/h) has recently been
reported on Cayo Largo, Cuba.

The estimated minimum central pressure is 985 mb (29.09 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 4 to 6 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...

Morgan City, LA to Mouth of the Mississippi River...10-15 ft
Mouth of the Mississippi River to Ocean Springs, MS including Lake
Borgne...7-11 ft
Intracoastal City, LA to Morgan City, LA including Vermilion
Bay...6-9 ft
Ocean Springs, MS to MS/AL border...4-7 ft
Lake Pontchartrain...4-7 ft
Lake Maurepas...3-5 ft
Pecan Island, LA to Intracoastal City, LA...3-5 ft
MS/AL border to AL/FL border including Mobile Bay...2-4 ft
Sabine Pass to Pecan Island, LA...2-4 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Hurricane and tropical storm conditions are occuring over
the Isle of Youth and portions of western Cuba and will continue
through tonight in western Cuba.

Hurricane conditions are expected in the hurricane warning area
along the northern Gulf coast beginning Sunday with tropical
storm conditions expected to begin by late Saturday night.

RAINFALL: Ida is expected to produce total rainfall accumulations
of 6 to 10 inches with maximum totals of 15 inches across Jamaica.
Rainfall totals of 8 to 12 inches with isolated maximum amounts of
20 inches are expected across the Cayman Islands and western Cuba,
including the Isle of Youth. These rainfall amounts may produce
life-threatening flash floods and mudslides.

As Ida approaches the central Gulf Coast Sunday afternoon, total
rainfall accumulations of 8 to 16 inches with isolated maximum
amounts of 20 inches are possible from southeast Louisiana to
coastal Mississippi and Alabama through Monday morning. This is
likely to result in considerable flash, urban, small stream, and
riverine flooding impacts.

Ida is forecast to turn northeast as it moves inland later Monday
with rainfall totals of 4 to 8 inches possible across southern and
central Mississippi into the Tennessee Valley. This is likely to
result in flash, urban, small stream, and riverine flooding impacts.

SURF: Swells generated by this system will affect the Cayman
Islands and Cuba through tonight. Swells will begin reaching
portions of the northern Gulf coast Saturday night or early Sunday.
These swells are likely to cause life-threatening surf and rip
current conditions. Please consult products from your local weather
office.


NEXT ADVISORY
-------------
Next intermediate advisory at 800 PM EDT.
Next complete advisory at 1100 PM EDT.

$$
Forecaster Brown



Hurricane Ida Discussion Number 6
NWS National Hurricane Center Miami FL AL092021
500 PM EDT Fri Aug 27 2021

Cuban radar data and reports from an earlier Air Force Reserve
Hurricane Hunter mission indicate that Ida's inner core structure
continued to improve after the release of the previous advisory
package. An eye became apparent in radar imagery before the center
reached the Isle of Youth, and the final fix from the Air Force
Hurricane Hunter aircraft reported a closed 24-n-mi wide eye. The
aircraft measured winds to support hurricane intensity shortly
before 1800 UTC, and during the final northeast eyewall pass, and
flight-level wind data support increasing the intensity to 70 kt,
which is used as the initial intensity for this advisory.

The upper-level outflow has expanded over all but the southwestern
portion of the circulation, and the upper-level wind pattern is
forecast to continue to improve overnight and early Saturday.
Once Ida moves past western Cuba and into the southeastern Gulf of
Mexico, it will be moving through a very favorable oceanic and
atmospheric environment consisting of high ocean heat content
waters, low vertical wind shear, and a moist low- to mid-level
atmosphere. These conditions are likely to result in a period
of rapid strengthening during the next 24 to 36 hours. In fact,
with the higher initial wind speed, the intensity guidance has
significantly increased this cycle, and the bulk of the guidance
now brings Ida to category 4 intensity. The NHC forecast explicitly
calls for rapid intensification during the next 24 to 36 hours,
which is supported by several of the dynamical models, the LGEM
model, and high probabilities of rapid intensification indicated
by the SHIPS and DTOPS RI guidance. The NHC forecast is near
the IVCN multi-model consensus aid, but is lower than HCCA and
LGEM. It should be noted that some fluctuations in intensity are
possible as Ida nears the northern Gulf coast due to possible
eyewall replacement cycles. In addition to the expected increase in
strength, the dynamical model guidance again calls for Ida's wind
field to expand while it moves over the Gulf of Mexico. As a
result, there is higher-than-normal confidence that a large and
powerful hurricane will impact portions of the northern Gulf coast
by late this weekend and early next week.

Ida has wobbled a little right of the previous track, but the longer
term motion continues to be northwestward or 320/13 kt. The steering
currents remain well-established as a strong deep-layer ridge over
the western Atlantic should continue to steer Ida northwestward
across the Gulf this weekend. Ida will approach the western
portion of the ridge after landfall, and this should result in a
slower northward motion by day 3. After that time, a short-wave
trough over the central United States is expected to cause the
system to turn northeastward. The track guidance remains in
remarkably good agreement through landfall along the northern Gulf
coast, and there is higher-than-normal confidence in that portion of
the track forecast. However, users are again reminded to not focus
on the exact details of the track forecast as storm surge, wind,
and rainfall impacts will extend far from the center.

Key Messages:

1. Life-threatening storm surge and hurricane conditions are
expected to continue through tonight in portions of western Cuba,
including the Isle of Youth, where a Hurricane Warning is in effect.
Life-threatening heavy rains, flash flooding and mudslides are
expected across Jamaica, the Cayman Islands, and western Cuba,
including the Isle of Youth.

2. There is a danger of life-threatening storm surge inundation
Sunday along the coasts of Louisiana and Mississippi within the
Storm Surge Warning area. Extremely life-threatening inundation of
10 to 15 feet above ground level is possible within the area from
Morgan City, Louisiana, to the Mouth of the Mississippi River.
Interests throughout the warning area should follow any advice given
by local officials.

3. Ida is expected to be an extremely dangerous major hurricane when
it reaches the coast of Louisiana. Hurricane-force winds are
expected Sunday in portions of the Hurricane Warning area along the
Louisiana coast, including metropolitan New Orleans, with
potentially catastrophic wind damage possible where the core of Ida
moves onshore. Actions to protect life and property should be rushed
to completion in the warning area.

4. Ida is likely to produce heavy rainfall later Sunday into Monday
across the central Gulf Coast from southeast Louisiana to coastal
Mississippi and Alabama, resulting in considerable flash, urban,
small stream, and riverine flooding impacts. As Ida moves inland,
flooding impacts are possible across portions of the Lower
Mississippi and Tennessee Valleys.

FORECAST POSITIONS AND MAX WINDS

INIT 27/2100Z 22.1N 83.2W 70 KT 80 MPH
12H 28/0600Z 23.5N 84.8W 85 KT 100 MPH
24H 28/1800Z 25.3N 86.9W 105 KT 120 MPH
36H 29/0600Z 27.1N 89.0W 115 KT 130 MPH
48H 29/1800Z 28.6N 90.6W 120 KT 140 MPH
60H 30/0600Z 30.0N 91.3W 80 KT 90 MPH...INLAND
72H 30/1800Z 31.5N 91.1W 40 KT 45 MPH...INLAND
96H 31/1800Z 34.4N 89.3W 30 KT 35 MPH...INLAND
120H 01/1800Z 36.0N 86.0W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Brown

[cycloneye]

Hurricane Ida Tropical Cyclone Update
NWS National Hurricane Center Miami FL AL092021
725 PM EDT Fri Aug 27 2021

...IDA MAKES LANDFALL IN PINAR DEL RIO CUBA...

Satellite images, radar data from Cuba, and data from the NOAA
Hurricane Hunters indicate that Ida has made landfall in the Cuban
province of Pinar Del Rio, about 20 miles (30 km) east of La
Coloma. Maximum sustained winds are estimated to be 80 mph (130
km/h).

SUMMARY OF 725 PM EDT...2325 UTC...INFORMATION
----------------------------------------------
LOCATION...22.3N 83.3W
ABOUT 85 MI...135 KM SW OF HAVANA CUBA
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...985 MB...29.09 INCHES

$$
Forecaster Cangialosi

[cycloneye]

BULLETIN
Hurricane Ida Intermediate Advisory Number 6A
NWS National Hurricane Center Miami FL AL092021
800 PM EDT Fri Aug 27 2021

...IDA INLAND OVER PINAR DEL RIO CUBA...
...FORECAST TO STRENGTHEN RAPIDLY THIS WEEKEND...


SUMMARY OF 800 PM EDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...22.4N 83.5W
ABOUT 90 MI...145 KM SW OF HAVANA CUBA
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...985 MB...29.09 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* East of Rockefeller Wildlife Refuge Louisiana to the
Mississippi/Alabama border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas

A Hurricane Warning is in effect for...
* Cuban provinces of Pinar del Rio and Artemisa, and the Isle of
Youth
* Intracoastal City Louisiana to the Mouth of the Pearl River
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Storm Surge Watch is in effect for...
* Sabine Pass to Rockefeller Wildlife Refuge Louisiana
* Mobile Bay

A Hurricane Watch is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Warning is in effect for...
* Cuban provinces of Matanzas, Mayabeque, and Havana
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov. This is a life-threatening situation. Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions. Promptly follow evacuation and other
instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of
tropical-storm-force winds, conditions that make outside
preparations difficult or dangerous. Preparations to protect life
and property should be rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere along the northern U.S. Gulf coast should
monitor the progress of this system. Interests in the Dry Tortugas
should also monitor the progress of Ida.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area
outside of the United States, please monitor products issued by
your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 800 PM EDT (0000 UTC), the center of Hurricane Ida was located
over western Cuba near latitude 22.4 North, longitude 83.5 West.
Ida is moving toward the northwest near 15 mph (24 km/h), and this
general motion should continue until Ida reaches the northern Gulf
coast on Sunday. A slower northward motion is forecast after Ida
reaches the northern Gulf coast. On the forecast track, the center
of Ida will remain over western Cuba for another hour or two, and
then move over the southeastern and central Gulf of Mexico later
tonight and Saturday. Ida is forecast to make landfall along the
U.S. northern Gulf coast within the hurricane warning area on
Sunday.

Maximum sustained winds are near 80 mph (130 km/h) with higher
gusts. Steady to rapid strengthening is expected when Ida moves
over the southeastern and central Gulf of Mexico over the weekend,
and Ida is expected to be an extremely dangerous major hurricane
when it approaches the northern Gulf coast on Sunday.

Hurricane-force winds extend outward up to 25 miles (35 km) from
the center and tropical-storm-force winds extend outward up to 90
miles (150 km). A wind gust to 46 mph (74 km/h) has recently been
reported on Cayo Largo, Cuba.

The estimated minimum central pressure is 985 mb (29.09 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 4 to 6 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...

Morgan City, LA to Mouth of the Mississippi River...10-15 ft
Mouth of the Mississippi River to Ocean Springs, MS including Lake
Borgne...7-11 ft
Intracoastal City, LA to Morgan City, LA including Vermilion
Bay...6-9 ft
Ocean Springs, MS to MS/AL border...4-7 ft
Lake Pontchartrain...4-7 ft
Lake Maurepas...3-5 ft
Pecan Island, LA to Intracoastal City, LA...3-5 ft
MS/AL border to AL/FL border including Mobile Bay...2-4 ft
Sabine Pass to Pecan Island, LA...2-4 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Hurricane and tropical storm conditions are occuring over
the Isle of Youth and portions of western Cuba and will continue
through tonight in western Cuba.

Hurricane conditions are expected in the hurricane warning area
along the northern Gulf coast beginning Sunday with tropical
storm conditions expected to begin by late Saturday night.

RAINFALL: Ida is expected to produce total rainfall accumulations
of 6 to 10 inches with maximum totals of 15 inches across Jamaica.
Rainfall totals of 8 to 12 inches with isolated maximum amounts of
20 inches are expected across the Cayman Islands and western Cuba,
including the Isle of Youth. These rainfall amounts may produce
life-threatening flash floods and mudslides.

As Ida approaches the central Gulf Coast Sunday afternoon, total
rainfall accumulations of 8 to 16 inches with isolated maximum
amounts of 20 inches are possible from southeast Louisiana to
coastal Mississippi and Alabama through Monday morning. This is
likely to result in considerable flash, urban, small stream, and
riverine flooding impacts.

Ida is forecast to turn northeast as it moves inland later Monday
with rainfall totals of 4 to 8 inches possible across southern and
central Mississippi into the Tennessee Valley. This is likely to
result in flash, urban, small stream, and riverine flooding impacts.

SURF: Swells generated by this system will affect the Cayman
Islands and Cuba through tonight. Swells will begin reaching
portions of the northern Gulf coast Saturday night or early Sunday.
These swells are likely to cause life-threatening surf and rip
current conditions. Please consult products from your local weather
office.


NEXT ADVISORY
-------------
Next complete advisory at 1100 PM EDT.

$$
Forecaster Cangialosi

[cycloneye]

BULLETIN
Hurricane Ida Advisory Number 7
NWS National Hurricane Center Miami FL AL092021
1100 PM EDT Fri Aug 27 2021

...IDA NOW ENTERING THE GULF OF MEXICO...
...FORECAST TO RAPIDLY INTENSIFY BEFORE REACHING THE NORTHERN GULF
COAST...


SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...23.0N 84.0W
ABOUT 105 MI...165 KM W OF HAVANA CUBA
ABOUT 615 MI...985 KM SE OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...989 MB...29.21 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* East of Rockefeller Wildlife Refuge Louisiana to the
Mississippi/Alabama border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas

A Hurricane Warning is in effect for...
* Cuban provinces of Pinar del Rio and Artemisa, and the Isle of
Youth
* Intracoastal City Louisiana to the Mouth of the Pearl River
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Storm Surge Watch is in effect for...
* Sabine Pass to Rockefeller Wildlife Refuge Louisiana
* Mobile Bay

A Hurricane Watch is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Warning is in effect for...
* Cuban provinces of Matanzas, Mayabeque, and Havana
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov. This is a life-threatening situation. Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions. Promptly follow evacuation and other
instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of
tropical-storm-force winds, conditions that make outside
preparations difficult or dangerous. Preparations to protect life
and property should be rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere along the northern U.S. Gulf coast should
monitor the progress of this system. Interests in the Dry Tortugas
should also monitor the progress of Ida.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area
outside of the United States, please monitor products issued by
your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 1100 PM EDT (0300 UTC), the center of Hurricane Ida was located
near latitude 23.0 North, longitude 84.0 West. Ida is moving toward
the northwest near 15 mph (24 km/h) and this general motion should
continue until Ida reaches the northern Gulf coast on Sunday. A
slower northward motion is forecast after Ida moves inland. On the
forecast track, the center of Ida will move over the southeastern
and central Gulf of Mexico during the next day or two and make
landfall along the U.S. northern Gulf coast within the hurricane
warning area by late Sunday.

Maximum sustained winds are near 80 mph (130 km/h) with higher
gusts. Rapid strengthening is forecast during the next day or two,
and Ida is expected to be an extremely dangerous major hurricane
when it approaches the northern Gulf coast on Sunday.

Hurricane-force winds extend outward up to 25 miles (35 km) from the
center and tropical-storm-force winds extend outward up to 115 miles
(185 km).

The estimated minimum central pressure based on data from the Air
Force Hurricane Hunters is 989 mb (29.21 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: A dangerous storm surge will raise water levels by
as much as 4 to 6 feet above normal tide levels in areas of onshore
winds along the immediate coast of the Isle of Youth and near and to
the east of where the center crosses the coast of western Cuba.
Near the coast, the surge will be accompanied by large and
destructive waves.

The combination of a dangerous storm surge and the tide will cause
normally dry areas near the coast to be flooded by rising waters
moving inland from the shoreline. The water could reach the
following heights above ground somewhere in the indicated areas if
the peak surge occurs at the time of high tide...

Morgan City, LA to Mouth of the Mississippi River...10-15 ft
Mouth of the Mississippi River to Ocean Springs, MS including Lake
Borgne...7-11 ft
Intracoastal City, LA to Morgan City, LA including Vermilion
Bay...6-9 ft
Ocean Springs, MS to MS/AL border...4-7 ft
Lake Pontchartrain...4-7 ft
Lake Maurepas...3-5 ft
Pecan Island, LA to Intracoastal City, LA...3-5 ft
MS/AL border to AL/FL border including Mobile Bay...2-4 ft
Sabine Pass to Pecan Island, LA...2-4 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Hurricane and tropical storm conditions are occuring over
the Isle of Youth and portions of western Cuba, and these winds
will continue for a few more hours.

Hurricane conditions are expected in the hurricane warning area
along the northern Gulf coast beginning Sunday with tropical
storm conditions expected to begin by late Saturday night or early
Sunday morning.

RAINFALL: Ida is expected to produce total rainfall accumulations
of 5 to 10 inches with isolated maximum amounts of 15 inches across
western Cuba, including the Isle of Youth. These rainfall amounts
may produce life-threatening flash floods and mudslides.

As Ida approaches the central Gulf Coast Sunday afternoon, total
rainfall accumulations of 8 to 16 inches with isolated maximum
amounts of 20 inches are possible across southeast Louisiana and
southern Mississippi through Monday. This is likely to result in
considerable flash and riverine flooding impacts.

Ida is forecast to turn northeast as it moves inland later Monday,
with rainfall totals of 4 to 8 inches possible from northeastern
Louisiana and central Mississippi into the Tennessee Valley. This is
likely to result in flash and riverine flooding impacts.

SURF: Swells generated by Ida will continue to affect western Cuba
through Saturday morning. Swells will begin reaching portions of
the northern Gulf coast Saturday night or early Sunday. These
swells are likely to cause life-threatening surf and rip current
conditions. Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 200 AM EDT.
Next complete advisory at 500 AM EDT.

$$
Forecaster Cangialosi



Hurricane Ida Discussion Number 7
NWS National Hurricane Center Miami FL AL092021
1100 PM EDT Fri Aug 27 2021

Ida made landfall in the Cuban province of Pinar Del Rio around
2320 UTC with maximum sustained winds estimated to be around 70 kt.
Radar data from Cuba indicate that the inner core of Ida has
remained intact after its passage over western Cuba with a
well-defined eye and relatively symmetric eyewall evident. In
addition, satellite images show deep convection increasing in both
intensity and coverage, a sign that Ida is strengthening. The Air
Force Hurricane Hunters are currently investigating Ida and so far
have found maximum 700 mb flight-level winds of 75 kt. Based on
that data, the initial intensity is held at 70 kt.

The hurricane is moving northwestward at about 13 kt. A subtropical
ridge centered off the southeast U.S. coast is expected to shift
westward through the weekend. This feature should continue to
provide a steering flow that will take Ida steadily northwestward
across the Gulf of Mexico during the next couple of days. The models
remain in very good agreement and show Ida making landfall in
Louisiana late Sunday or early Monday morning. After the storm moves
inland, a decrease in forward speed and a turn to the north and then
the northeast is predicted as Ida moves in the flow on the northwest
and north sides of the ridge. Since the models are tightly clustered
and because the steering flow is well pronounced, there is high
confidence in the track forecast. The new NHC track forecast is very
similar to the previous one and near the various consensus aids,
which are often the most accurate models. Users are again reminded
to not focus on the exact details of the track forecast as storm
surge, wind, and rainfall impacts will extend far from the center.

Ida is expected to remain in conducive conditions for
intensification until it reaches the central Gulf coast. The global
models show a very favorable upper-level wind pattern over the storm
and abundant environmental moisture. These conducive atmospheric
conditions combined with very warm Gulf of Mexico waters should
allow Ida to rapidly intensify this weekend. In fact, it seems
likely that Ida will pass over a warm eddy over the central Gulf of
Mexico, where the ocean heat content is very high. All of the
models show significant strengthening, but there is a fair amount of
spread on how strong the hurricane will get. The NHC intensity
forecast remains near the high end of the model guidance, and shows
Ida becoming an extremely dangerous category 4 hurricane prior to
reaching the coast. After landfall, rapid weakening is expected due
to land interaction, drier air, and an increase in shear.

As Ida continues to intensify over the Gulf of Mexico, an expansion
of its wind field is predicted. The NHC wind radii forecast is
largely based on the radii consensus, and winds of at least tropical
storm force are likely to reach the coast Sunday morning. Therefore,
all preparations to protect life and property for this dangerous
event need to be made on Saturday.


Key Messages:

1. Life-threatening storm surge and hurricane conditions are
expected to continue for the next few hours in portions of western
Cuba, including the Isle of Youth, where a Hurricane Warning is in
effect. Life-threatening heavy rains, flash flooding and mudslides
are expected across Jamaica, the Cayman Islands, and western Cuba,
including the Isle of Youth.

2. There is a danger of life-threatening storm surge inundation
Sunday along the coasts of Louisiana and Mississippi within the
Storm Surge Warning area. Extremely life-threatening inundation of
10 to 15 feet above ground level is possible within the area from
Morgan City, Louisiana, to the Mouth of the Mississippi River.
Interests throughout the warning area should follow any advice given
by local officials.

3. Ida is expected to be an extremely dangerous major hurricane when
it reaches the coast of Louisiana. Hurricane-force winds are
expected Sunday in portions of the Hurricane Warning area along the
Louisiana coast, including metropolitan New Orleans, with
potentially catastrophic wind damage possible where the core of Ida
moves onshore. Actions to protect life and property should be rushed
to completion in the warning area.

4. Ida is likely to produce heavy rainfall later Sunday into Monday
across the central Gulf Coast from southeast Louisiana to coastal
Mississippi and Alabama, resulting in considerable flash, urban,
small stream, and riverine flooding impacts. As Ida moves inland,
flooding impacts are possible across portions of the Lower
Mississippi and Tennessee Valleys.


FORECAST POSITIONS AND MAX WINDS

INIT 28/0300Z 23.0N 84.0W 70 KT 80 MPH
12H 28/1200Z 24.4N 85.6W 85 KT 100 MPH
24H 29/0000Z 26.1N 87.7W 105 KT 120 MPH
36H 29/1200Z 27.8N 89.6W 120 KT 140 MPH
48H 30/0000Z 29.2N 90.8W 110 KT 125 MPH...INLAND
60H 30/1200Z 30.7N 91.0W 60 KT 70 MPH...INLAND
72H 31/0000Z 32.3N 90.6W 35 KT 40 MPH...INLAND
96H 01/0000Z 34.9N 88.2W 25 KT 30 MPH...INLAND
120H 02/0000Z 36.8N 83.9W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Cangialosi

[cycloneye]

BULLETIN
Hurricane Ida Advisory Number 8...Corrected
NWS National Hurricane Center Miami FL AL092021
400 AM CDT Sat Aug 28 2021

Corrected Storm Surge Hazard Section

...IDA CONTINUES MOVING NORTHWESTWARD ACROSS THE SOUTHEASTERN
GULF OF MEXICO...
...FORECAST TO RAPIDLY INTENSIFY BEFORE REACHING THE NORTHERN GULF
COAST...


SUMMARY OF 400 AM CDT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...24.0N 85.2W
ABOUT 510 MI...825 KM SE OF NEW ORLEANS LOUISIANA
ABOUT 185 MI...300 KM WNW OF HAVANA CUBA
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...987 MB...29.15 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The Government of Cuba has discontinued all warnings for Cuba.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* East of Rockefeller Wildlife Refuge Louisiana to the
Mississippi/Alabama border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas

A Hurricane Warning is in effect for...
* Intracoastal City Louisiana to the Mouth of the Pearl River
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Storm Surge Watch is in effect for...
* Sabine Pass to Rockefeller Wildlife Refuge Louisiana
* Mobile Bay

A Hurricane Watch is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Warning is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov. This is a life-threatening situation. Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions. Promptly follow evacuation and other
instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of
tropical-storm-force winds, conditions that make outside
preparations difficult or dangerous. Preparations to protect life
and property should be rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere along the northern U.S. Gulf coast should
monitor the progress of this system.

For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


DISCUSSION AND OUTLOOK
----------------------
At 400 AM CDT (0900 UTC), the center of Hurricane Ida was located
near latitude 24.0 North, longitude 85.2 West. Ida is moving toward
the northwest near 16 mph (26 km/h) and this general motion should
continue through late Sunday or early Monday. A slower northward
motion is forecast on Monday. On the forecast track, the center of
Ida will move over the southeastern Gulf of Mexico today and over
the north central Gulf of Mexico on Sunday. Ida is then expected
to make landfall along the U.S. northern Gulf coast within the
hurricane warning area by late Sunday or early Monday, then move
through portions of Louisiana or western Mississippi later on
Monday.

Maximum sustained winds are near 80 mph (130 km/h) with higher
gusts. Rapid strengthening is forecast during the next 24 to 36
hours and Ida is expected to be an extremely dangerous major
hurricane when it approaches the northern Gulf coast on Sunday.
Weakening is expected after Ida makes landfall.

Hurricane-force winds extend outward up to 25 miles (35 km) from the
center and tropical-storm-force winds extend outward up to 115 miles
(185 km).

The estimated minimum central pressure is 987 mb (29.15 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline. The water could
reach the following heights above ground somewhere in the indicated
areas if the peak surge occurs at the time of high tide...

Morgan City, LA to Mouth of the Mississippi River...10-15 ft
Mouth of the Mississippi River to Ocean Springs, MS including Lake
Borgne...7-11 ft
Intracoastal City, LA to Morgan City, LA including Vermilion
Bay...6-9 ft
Ocean Springs, MS to MS/AL border...4-7 ft
Lake Pontchartrain...4-7 ft
Lake Maurepas...3-5 ft
Pecan Island, LA to Intracoastal City, LA...3-5 ft
MS/AL border to AL/FL border including Mobile Bay...2-4 ft
Sabine Pass to Pecan Island, LA...2-4 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Hurricane conditions are expected in the hurricane warning
area along the northern Gulf coast beginning Sunday with tropical
storm conditions expected to begin by late Saturday night or early
Sunday morning. These conditions will spread inland over portions
of Louisiana and Mississippi Sunday night and Monday. Gusty winds
are possible over portions of western Cuba and the Florida Keys
this morning.

RAINFALL: Ida will continue to lift north of Cuba this morning
bringing an additional 2 to 4 inches of rain with isolated maximum
amounts of 6 inches across western Cuba through today. These
rainfall amounts may produce flash floods and mudslides.

As Ida moves into the Louisiana coast late Sunday, total rainfall
accumulations of 8 to 16 inches with isolated maximum amounts of 20
inches are possible across southeast Louisiana and southern
Mississippi through Monday. This is likely to result in significant
flash and riverine flooding impacts.

Ida is forecast to turn northeast as it moves inland later Monday,
with rainfall totals of 4 to 8 inches possible from northeastern
Louisiana and central Mississippi into the Tennessee Valley. This is
likely to result in considerable flash and riverine flooding
impacts.

TORNADOES: A few tornadoes will be possible Sunday through early
Monday across southeast Louisiana and southern Mississippi.

SURF: Swells generated by Ida will continue to affect western Cuba
through Saturday morning. Swells will begin reaching portions of
the northern Gulf coast Saturday night or early Sunday. These
swells are likely to cause life-threatening surf and rip current
conditions. Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 700 AM CDT.
Next complete advisory at 1000 AM CDT.

$$
Forecaster Beven



Hurricane Ida Discussion Number 8
NWS National Hurricane Center Miami FL AL092021
400 AM CDT Sat Aug 28 2021

Just after the last advisory, the convective structure of Ida got a
bit ragged, probably due to the residual effects of land
interaction with Cuba and a tongue of dry air that wrapped into the
eastern side of the circulation. However, latest radar images from
Cuba show that the eye is becoming better defined, and satellite
imagery shows cooling of the cloud tops in the eyewall. The
initial intensity has been held at 70 kt based on the latest trends
and earlier Hurricane Hunter aircraft data. NOAA and Air Force
reserve Hurricane Hunter aircraft are scheduled to investigate Ida
again starting around 12Z.

The initial motion remains northwestward or 315/14. A subtropical
ridge centered off the southeast U.S. coast is expected to shift
westward through the weekend, and this feature should continue to
provide a steering flow that will take Ida steadily northwestward
across the Gulf of Mexico during the next 36-48 h. The track
guidance remains in good agreement that Ida will make landfall on
the coast of southeastern or central Louisiana late Sunday or early
Monday morning. After landfall, Ida is expected to turn northward
through Louisiana and western Mississippi at a slower forward speed
as it moves around the western end of the ridge. Recurvature into
the westerlies and an east-northeastward motion are expected by the
end of the forecast period. The new forecast track is nudged
slightly to the west after 36 h to keep it near the various
consensus models, but this is not a significant change from the
previous forecast. Users are again reminded to not focus on the
exact details of the track forecast as storm surge, wind, and
rainfall impacts will extend far from the center.

Ida is expected to remain in a favorable environment of light
vertical shear and very warm sea-surface temperatures until it
makes landfall. The only negative factor is the possibility that
dry air may try to entrain into the system and slow the expected
intensification. The SHIPS and LGEM models are showing a little
less strengthening than previously. However, the HWRF and HMON
models continue to forecast Ida to reach Category 4 intensity
before landfall. The new intensity forecast will forecast a peak
intensity of 120 kt in best agreement with the HWRF and HMON, and
the pre-landfall part of the forecast is little changed from the
previous forecast. After landfall, rapid weakening is expected due
to land interaction, drier air, and an increase in shear, and Ida
is expected to become a post-tropical cyclone as it moves through
the Tennessee Valley.

As Ida continues to intensify over the Gulf of Mexico, an expansion
of its wind field is predicted. The NHC wind radii forecast is
largely based on the radii consensus, and winds of at least tropical
storm force are likely to reach the coast Sunday morning. Therefore,
all preparations to protect life and property for this dangerous
event need to be made today.


Key Messages:

1. Hurricane and tropical storm conditions are ending over Cuba.
However, Ida will continue to bring periods of heavy rain across
western Cuba through today that may lead to flash flooding and
mudslides.

2. There is a danger of life-threatening storm surge inundation
Sunday along the coasts of Louisiana and Mississippi within the
Storm Surge Warning area. Extremely life-threatening inundation of
10 to 15 feet above ground level is possible within the area from
Morgan City, Louisiana, to the Mouth of the Mississippi River.
Interests throughout the warning area should follow any advice given
by local officials.

3. Ida is expected to be an extremely dangerous major hurricane when
it reaches the coast of Louisiana. Hurricane-force winds are
expected Sunday in portions of the Hurricane Warning area along the
Louisiana coast, including metropolitan New Orleans, with
potentially catastrophic wind damage possible where the core of Ida
moves onshore. Actions to protect life and property should be rushed
to completion in the warning area.

4. Ida is likely to produce heavy rainfall later Sunday into Monday
across the central Gulf Coast from southeast Louisiana to coastal
Mississippi resulting in significant flash and riverine flooding
impacts. As Ida moves inland, flooding impacts are possible across
portions of the Lower Mississippi and Tennessee Valleys.


FORECAST POSITIONS AND MAX WINDS

INIT 28/0900Z 24.0N 85.2W 70 KT 80 MPH
12H 28/1800Z 25.4N 86.9W 85 KT 100 MPH
24H 29/0600Z 27.1N 88.9W 105 KT 120 MPH
36H 29/1800Z 28.6N 90.5W 120 KT 140 MPH
48H 30/0600Z 30.1N 91.3W 85 KT 100 MPH...INLAND
60H 30/1800Z 31.6N 91.2W 45 KT 50 MPH...INLAND
72H 31/0600Z 33.2N 90.5W 30 KT 35 MPH...INLAND
96H 01/0600Z 36.0N 87.0W 25 KT 30 MPH...INLAND
120H 02/0600Z 37.5N 82.5W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Beven

[cycloneye]

BULLETIN
Hurricane Ida Intermediate Advisory Number 8A
NWS National Hurricane Center Miami FL AL092021
700 AM CDT Sat Aug 28 2021

...IDA EXPECTED TO RAPIDLY INTENSIFY AS IT MOVES OVER THE
SOUTHEASTERN AND CENTRAL GULF OF MEXICO THROUGH TONIGHT...
...PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED TO
COMPLETION TODAY IN THE WARNING AREA ALONG THE NORTHERN GULF
COAST...


SUMMARY OF 700 AM CDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...24.4N 85.7W
ABOUT 385 MI...620 KM SSE OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 440 MI...710 KM SSE OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...985 MB...29.09 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* East of Rockefeller Wildlife Refuge Louisiana to the
Mississippi/Alabama border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas

A Hurricane Warning is in effect for...
* Intracoastal City Louisiana to the Mouth of the Pearl River
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Storm Surge Watch is in effect for...
* Sabine Pass to Rockefeller Wildlife Refuge Louisiana
* Mobile Bay

A Hurricane Watch is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Warning is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Mississippi/Alabama border

A Tropical Storm Watch is in effect for...
* Mississippi/Alabama border to the Alabama/Florida border

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov. This is a life-threatening situation. Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions. Promptly follow evacuation and other
instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of
tropical-storm-force winds, conditions that make outside
preparations difficult or dangerous. Preparations to protect life
and property should be rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

Interests elsewhere along the northern U.S. Gulf coast should
monitor the progress of this system.

For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


DISCUSSION AND OUTLOOK
----------------------
At 700 AM CDT (1200 UTC), the center of Hurricane Ida was located
near latitude 24.4 North, longitude 85.7 West. Ida is moving toward
the northwest near 16 mph (26 km/h) and this general motion should
continue through late Sunday or early Monday, followed by a slower
northward motion on Monday. On the forecast track, the center of
Ida will move over the southeastern Gulf of Mexico today and move
over the central Gulf of Mexico tonight and early Sunday. Ida is
then expected to make landfall along the U.S. northern Gulf coast
within the hurricane warning area on Sunday, and then move inland
over portions of Louisiana or western Mississippi later on Monday.

Maximum sustained winds have increased to near 85 mph (140 km/h)
with higher gusts. Rapid strengthening is forecast during the next
24 to 36 hours and Ida is expected to be an extremely dangerous
major hurricane when it approaches the northern Gulf coast on
Sunday. Weakening is expected after Ida makes landfall.

Hurricane-force winds extend outward up to 25 miles (35 km) from
the center and tropical-storm-force winds extend outward up to 115
miles (185 km).

The latest minimum central pressure estimated from NOAA
reconnaissance aircraft data is 985 mb (29.09 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline. The water could
reach the following heights above ground somewhere in the indicated
areas if the peak surge occurs at the time of high tide...

Morgan City, LA to Mouth of the Mississippi River...10-15 ft
Mouth of the Mississippi River to Ocean Springs, MS including Lake
Borgne...7-11 ft
Intracoastal City, LA to Morgan City, LA including Vermilion
Bay...6-9 ft
Ocean Springs, MS to MS/AL border...4-7 ft
Lake Pontchartrain...4-7 ft
Lake Maurepas...3-5 ft
Pecan Island, LA to Intracoastal City, LA...3-5 ft
MS/AL border to AL/FL border including Mobile Bay...2-4 ft
Sabine Pass to Pecan Island, LA...2-4 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle,
and can vary greatly over short distances. For information
specific to your area, please see products issued by your local
National Weather Service forecast office.

WIND: Hurricane conditions are expected in the hurricane warning
area along the northern Gulf coast beginning Sunday with tropical
storm conditions expected to begin by late Saturday night or early
Sunday morning. These conditions will spread inland over portions
of Louisiana and Mississippi Sunday night and Monday. Gusty winds
are possible over portions of western Cuba and the Florida Keys
this morning.

RAINFALL: Ida will bring an additional 2 to 4 inches of rain
with isolated maximum amounts of 6 inches across western Cuba
today. These rainfall amounts may produce flash floods and
mudslides.

As Ida moves into the Louisiana coast late Sunday, total rainfall
accumulations of 8 to 16 inches with isolated maximum amounts of 20
inches are possible across southeast Louisiana and southern
Mississippi through Monday. This rainfall is likely to result in
significant flash and riverine flooding impacts.

Ida is forecast to turn northeast as it moves inland later Monday,
with rainfall totals of 4 to 8 inches possible from northeastern
Louisiana and central Mississippi into the Tennessee Valley. This is
likely to result in considerable flash and riverine flooding
impacts.

TORNADOES: A few tornadoes will be possible Sunday through early
Monday across southeast Louisiana and southern Mississippi.

SURF: Swells generated by Ida will continue to affect western Cuba
through today. Swells will begin reaching portions of the northern
Gulf coast later today and continue through Monday. These swells
are likely to cause life-threatening surf and rip current
conditions. Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next complete advisory at 1000 AM CDT.

$$
Forecaster Brown

[AlphaToOmega]

000
WTNT34 KNHC 281451
TCPAT4

BULLETIN
Hurricane Ida Advisory Number 9
NWS National Hurricane Center Miami FL AL092021
1000 AM CDT Sat Aug 28 2021

...IDA EXPECTED TO BEGIN RAPIDLY INTENSIFYING SOON...
...PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED TO
COMPLETION TODAY IN THE WARNING AREA ALONG THE NORTHERN GULF
COAST...


SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...24.8N 86.1W
ABOUT 350 MI...565 KM SSE OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 435 MI...700 KM SE OF HOUMA LOUISIANA
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...984 MB...29.06 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The Tropical Storm Warning has been extended eastward along the
northern Gulf coast to the Alabama/Florida border.

The Hurricane Watch along the coast of Mississippi from the Mouth
of the Pearl River to the Mississippi/Alabama border has been
discontinued. The Hurricane Watch along the coast of Louisiana
west of Intracoastal City has also been discontinued.

The Storm Surge Watch from Sabine Pass to Rockefeller Wildlife
Refuge, Louisiana has been discontinued.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* East of Rockefeller Wildlife Refuge Louisiana to the
Mississippi/Alabama border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas

A Hurricane Warning is in effect for...
* Intracoastal City Louisiana to the Mouth of the Pearl River
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Storm Surge Watch is in effect for...
* Mobile Bay

A Tropical Storm Warning is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Alabama/Florida border

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov. This is a life-threatening situation. Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions. Promptly follow evacuation and other
instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of
tropical-storm-force winds, conditions that make outside
preparations difficult or dangerous. Preparations to protect life
and property should be rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


DISCUSSION AND OUTLOOK
----------------------
At 1000 AM CDT (1500 UTC), the center of Hurricane Ida was located
near latitude 24.8 North, longitude 86.1 West. Ida is moving toward
the northwest near 16 mph (26 km/h), and this general motion should
continue through late Sunday or early Monday, followed by a slower
northward motion on Monday. On the forecast track, the center of
Ida will move over the southeastern Gulf of Mexico today and move
over the central Gulf of Mexico tonight and early Sunday. Ida is
then expected to make landfall along the U.S. northern Gulf coast
within the hurricane warning area on Sunday, and then move inland
over portions of Louisiana or western Mississippi later on Monday.

Maximum sustained winds are near 85 mph (140 km/h) with higher
gusts. Rapid strengthening is forecast during the next 24 to 36
hours and Ida is expected to be an extremely dangerous major
hurricane when it approaches the northern Gulf coast on Sunday.
Weakening is expected after Ida makes landfall.

Hurricane-force winds extend outward up to 30 miles (45 km) from the
center and tropical-storm-force winds extend outward up to 125 miles
(205 km).

The latest minimum central pressure estimated from Air Force
Reserve reconnaissance aircraft data is 984 mb (29.06 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline. The water could
reach the following heights above ground somewhere in the indicated
areas if the peak surge occurs at the time of high tide...

Morgan City, LA to Mouth of the Mississippi River...10-15 ft
Mouth of the Mississippi River to Ocean Springs, MS including Lake
Borgne...7-11 ft
Intracoastal City, LA to Morgan City, LA including Vermilion
Bay...6-9 ft
Ocean Springs, MS to MS/AL border...4-7 ft
Lake Pontchartrain...4-7 ft
Lake Maurepas...3-5 ft
Pecan Island, LA to Intracoastal City, LA...3-5 ft
MS/AL border to AL/FL border including Mobile Bay...2-4 ft
Sabine Pass to Pecan Island, LA...1-3 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle, and
can vary greatly over short distances. For information specific to
your area, please see products issued by your local National Weather
Service forecast office.

WIND: Hurricane conditions are expected in the hurricane warning
area along the Louisiana coast beginning Sunday with tropical storm
conditions expected to begin by late tonight or early Sunday
morning. These conditions will spread inland over portions of
Louisiana and Mississippi Sunday night and Monday.

RAINFALL: Heavy rainfall from Ida will begin to impact the
Louisiana coast Sunday morning, spreading northeast into the Lower
Mississippi Valley later Sunday into Monday. Total rainfall
accumulations of 8 to 16 inches with isolated maximum amounts of 20
inches are possible across southeast Louisiana and southern
Mississippi through Monday. This is likely to result in
life-threatening flash and urban flooding impacts and significant
riverine flooding impacts.

Ida is forecast to turn northeast later Monday, with rainfall totals
of 4 to 8 inches possible from northeastern Louisiana and central
Mississippi into the Tennessee Valley. This is likely to result in
considerable flash and riverine flooding impacts.

Rainfall impacts from Ida will diminish across western Cuba today
as the storm continues to lift northward away from the island. An
additional 1 to 2 inches of rain with isolated maximum amounts of 4
inches are possible across western Cuba through today. These
rainfall amounts may produce flash floods and mudslides.

TORNADOES: Tornadoes will be possible Sunday into Monday across
the northern Gulf coast states including parts of eastern
Louisiana, Mississippi, central and southern Alabama, and the
Florida Panhandle. The longest duration tornado threat will exist
across southeast Louisiana and southern Mississippi.

SURF: Swells generated by Ida will continue to affect western Cuba
through today. Swells will begin reaching portions of the northern
Gulf coast later today and continue through Monday. These swells
are likely to cause life-threatening surf and rip current
conditions. Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 100 PM CDT.
Next complete advisory at 400 PM CDT.

$$
Forecaster Brown

[cycloneye]

BULLETIN
Hurricane Ida Advisory Number 9
NWS National Hurricane Center Miami FL AL092021
1000 AM CDT Sat Aug 28 2021

...IDA EXPECTED TO BEGIN RAPIDLY INTENSIFYING SOON...
...PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED TO
COMPLETION TODAY IN THE WARNING AREA ALONG THE NORTHERN GULF
COAST...


SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...24.8N 86.1W
ABOUT 350 MI...565 KM SSE OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 435 MI...700 KM SE OF HOUMA LOUISIANA
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...984 MB...29.06 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

The Tropical Storm Warning has been extended eastward along the
northern Gulf coast to the Alabama/Florida border.

The Hurricane Watch along the coast of Mississippi from the Mouth
of the Pearl River to the Mississippi/Alabama border has been
discontinued. The Hurricane Watch along the coast of Louisiana
west of Intracoastal City has also been discontinued.

The Storm Surge Watch from Sabine Pass to Rockefeller Wildlife
Refuge, Louisiana has been discontinued.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* East of Rockefeller Wildlife Refuge Louisiana to the
Mississippi/Alabama border
* Vermilion Bay, Lake Borgne, Lake Pontchartrain, and Lake Maurepas

A Hurricane Warning is in effect for...
* Intracoastal City Louisiana to the Mouth of the Pearl River
* Lake Pontchartrain, Lake Maurepas, and Metropolitan New Orleans

A Storm Surge Watch is in effect for...
* Mobile Bay

A Tropical Storm Warning is in effect for...
* Cameron Louisiana to west of Intracoastal City Louisiana
* Mouth of the Pearl River to the Alabama/Florida border

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov. This is a life-threatening situation. Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions. Promptly follow evacuation and other
instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. A warning is typically issued
36 hours before the anticipated first occurrence of
tropical-storm-force winds, conditions that make outside
preparations difficult or dangerous. Preparations to protect life
and property should be rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area within 36 hours.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


DISCUSSION AND OUTLOOK
----------------------
At 1000 AM CDT (1500 UTC), the center of Hurricane Ida was located
near latitude 24.8 North, longitude 86.1 West. Ida is moving toward
the northwest near 16 mph (26 km/h), and this general motion should
continue through late Sunday or early Monday, followed by a slower
northward motion on Monday. On the forecast track, the center of
Ida will move over the southeastern Gulf of Mexico today and move
over the central Gulf of Mexico tonight and early Sunday. Ida is
then expected to make landfall along the U.S. northern Gulf coast
within the hurricane warning area on Sunday, and then move inland
over portions of Louisiana or western Mississippi later on Monday.

Maximum sustained winds are near 85 mph (140 km/h) with higher
gusts. Rapid strengthening is forecast during the next 24 to 36
hours and Ida is expected to be an extremely dangerous major
hurricane when it approaches the northern Gulf coast on Sunday.
Weakening is expected after Ida makes landfall.

Hurricane-force winds extend outward up to 30 miles (45 km) from the
center and tropical-storm-force winds extend outward up to 125 miles
(205 km).

The latest minimum central pressure estimated from Air Force
Reserve reconnaissance aircraft data is 984 mb (29.06 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Ida can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC,
and on the web at hurricanes.gov/graphics_at4.shtml?key_messages.

STORM SURGE: The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline. The water could
reach the following heights above ground somewhere in the indicated
areas if the peak surge occurs at the time of high tide...

Morgan City, LA to Mouth of the Mississippi River...10-15 ft
Mouth of the Mississippi River to Ocean Springs, MS including Lake
Borgne...7-11 ft
Intracoastal City, LA to Morgan City, LA including Vermilion
Bay...6-9 ft
Ocean Springs, MS to MS/AL border...4-7 ft
Lake Pontchartrain...4-7 ft
Lake Maurepas...3-5 ft
Pecan Island, LA to Intracoastal City, LA...3-5 ft
MS/AL border to AL/FL border including Mobile Bay...2-4 ft
Sabine Pass to Pecan Island, LA...1-3 ft

Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher than those shown above.

The deepest water will occur along the immediate coast near and to
the east of the landfall location, where the surge will be
accompanied by large and dangerous waves. Surge-related flooding
depends on the relative timing of the surge and the tidal cycle, and
can vary greatly over short distances. For information specific to
your area, please see products issued by your local National Weather
Service forecast office.

WIND: Hurricane conditions are expected in the hurricane warning
area along the Louisiana coast beginning Sunday with tropical storm
conditions expected to begin by late tonight or early Sunday
morning. These conditions will spread inland over portions of
Louisiana and Mississippi Sunday night and Monday.

RAINFALL: Heavy rainfall from Ida will begin to impact the
Louisiana coast Sunday morning, spreading northeast into the Lower
Mississippi Valley later Sunday into Monday. Total rainfall
accumulations of 8 to 16 inches with isolated maximum amounts of 20
inches are possible across southeast Louisiana and southern
Mississippi through Monday. This is likely to result in
life-threatening flash and urban flooding impacts and significant
riverine flooding impacts.

Ida is forecast to turn northeast later Monday, with rainfall totals
of 4 to 8 inches possible from northeastern Louisiana and central
Mississippi into the Tennessee Valley. This is likely to result in
considerable flash and riverine flooding impacts.

Rainfall impacts from Ida will diminish across western Cuba today
as the storm continues to lift northward away from the island. An
additional 1 to 2 inches of rain with isolated maximum amounts of 4
inches are possible across western Cuba through today. These
rainfall amounts may produce flash floods and mudslides.

TORNADOES: Tornadoes will be possible Sunday into Monday across
the northern Gulf coast states including parts of eastern
Louisiana, Mississippi, central and southern Alabama, and the
Florida Panhandle. The longest duration tornado threat will exist
across southeast Louisiana and southern Mississippi.

SURF: Swells generated by Ida will continue to affect western Cuba
through today. Swells will begin reaching portions of the northern
Gulf coast later today and continue through Monday. These swells
are likely to cause life-threatening surf and rip current
conditions. Please consult products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 100 PM CDT.
Next complete advisory at 400 PM CDT.

$$
Forecaster Brown



Hurricane Ida Discussion Number 9
NWS National Hurricane Center Miami FL AL092021
1000 AM CDT Sat Aug 28 2021

The satellite presentation of Ida has continued to improve this
morning with the center embedded within a fairly symmetric Central
Dense Overcast and hints of the eye in both visible in infrared
satellite imagery. Earlier microwave imagery revealed a well-
defined low- to mid-level eye and excellent spiral banding over the
northern semicircle. Both NOAA and Air Force Reserve hurricane
hunter aircraft, somewhat surprisingly, have not found a
significantly deepening tropical cyclone yet, but given the very
recent increase in organization and structure, the winds are likely
to catch up to the satellite appearance very soon. Using the latest
flight-level and SFMR wind data from the aircraft and satellite
intensity estimates the initial wind speed remains 75 kt for this
advisory. The aircraft data does indicate that Ida's wind field has
expanded, and the NHC wind radii have been adjusted accordingly.

Given the improved inner-core structure Ida appears poised to
rapidly intensify during the next 12 to 24 hours as it remains
within a favorable environment of low vertical wind shear and over
warm water. Although the interpolated intensity guidance has
lowered somewhat due to the fact that Ida has not significantly
strengthened yet, the explicit forecasts from the dynamical models
continue to support significant deepening, and the latest runs of
the HWRF and HMON models indicate Ida will reach Category 4 strength
before landfall. The new NHC intensity forecast calls for rapid
intensification to Category 4 strength during the next 24 hours.
After that time, fluctuations in intensity are possible due to
eyewall replacement cycles as Ida approaches the northern Gulf
coast. After landfall, rapid weakening is expected and Ida is
forecast to weaken to a tropical depression by Monday night, and
become a post-tropical cyclone as it moves over the Tennessee Valley
by mid-week.

Ida has been moving steadily northwestward or 315/14 kt. A deep
layer ridge near the southeastern United States coast is forecast to
shift westward during the next day or so, and this should continue
to steer Ida northwestward through landfall on Sunday. The track
guidance remains in remarkably good agreement through 36 hours, and
the new NHC track forecast is essentially unchanged during that
time, and continues to indicate that Ida will reach the coast of
Louisiana on Sunday. After landfall, Ida will be near the western
extent of the ridge and should turn northward and then northeastward
as it recurves into the southern portion of the mid-latitude
westerlies. The track guidance has shifted slightly westward beyond
48 hours, and the track forecast over the southern U.S. and the
Tennessee Valley has been adjusted accordingly. Users are again
reminded to not focus on the exact details of the track forecast as
storm surge, wind, and rainfall impacts will extend far from the
center. Wind and rainfall impacts will also penetrate inland
through early next week after Ida makes landfall.

Key Messages:

1. There is a danger of life-threatening storm surge inundation
Sunday along the coasts of Louisiana and Mississippi within the
Storm Surge Warning area. Extremely life-threatening inundation of
9 feet or greater above ground level is possible somewhere within
the area from Morgan City, Louisiana, to the coast of Mississippi.
Overtopping of local levees outside of the Hurricane and Storm
Damage Risk Reduction System is possible where local inundation
values may be higher. Interests throughout the warning area should
follow any advice given by local officials.

2. Ida is expected to be an extremely dangerous major hurricane when
it reaches the coast of Louisiana. Hurricane-force winds are
expected Sunday in portions of the Hurricane Warning area along the
Louisiana coast, including metropolitan New Orleans, with
potentially catastrophic wind damage possible where the core of Ida
moves onshore. Actions to protect life and property should be rushed
to completion today in the warning area.

3. Ida is likely to produce heavy rainfall Sunday and Monday across
the central Gulf Coast from southeast Louisiana to coastal
Mississippi, resulting in life-threatening flash and urban flooding
and significant river flooding impacts. As Ida moves inland,
significant flooding impacts are likely across portions of the Lower
Mississippi and Tennessee Valleys Monday and Tuesday.

FORECAST POSITIONS AND MAX WINDS

INIT 28/1500Z 24.8N 86.1W 75 KT 85 MPH
12H 29/0000Z 26.3N 87.9W 100 KT 115 MPH
24H 29/1200Z 28.0N 89.8W 115 KT 130 MPH
36H 30/0000Z 29.4N 91.0W 115 KT 130 MPH...INLAND
48H 30/1200Z 31.0N 91.5W 60 KT 70 MPH...INLAND
60H 31/0000Z 32.7N 91.0W 30 KT 35 MPH...INLAND
72H 31/1200Z 34.4N 89.8W 25 KT 30 MPH...INLAND
96H 01/1200Z 36.8N 85.3W 20 KT 25 MPH...POST-TROP/INLAND
120H 02/1200Z 37.9N 79.9W 20 KT 25 MPH...POST-TROP/INLAND

$$
Forecaster Brown