EPAC: OTTO - Remnants

[Alyono]

new MU is also much weaker. This may not intensify much more than it currently is

[Hammy]

Otto is looking quite disorganized and is probably below hurricane intensity at the moment.

[wxmann_91]

I wouldn't be surprised if upwelling, dry air, and lingering southeasterly shear all had to do with tonight's weakening phase. Small cyclones are sensitive to even slight changes.

[Alyono]

One interesting thing. Cesar and Joan both weakened in this area and then intensified quite a bit near Nicaragua. I wonder if something similar will happen.

[Digital-TC-Chaser]

0z EC hi-res was showing 981mb @lanfall.

[arlwx]

HURRICANE OTTO ADVISORY NUMBER 10
NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016
400 AM EST WED NOV 23 2016

...OTTO SLOWLY HEADING TOWARD COSTA RICA AND NICARAGUA...


SUMMARY OF 400 AM EST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...10.9N 80.4W
ABOUT 185 MI...300 KM ENE OF LIMON COSTA RICA
ABOUT 240 MI...390 KM ESE OF BLUEFIELDS NICARAGUA
MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 5 MPH...7 KM/H
MINIMUM CENTRAL PRESSURE...988 MB...29.18 INCHES


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

The Government of Nicaragua has issued a Tropical Storm Watch for
the Pacific coast from Puerto Sandino to Santa Elena.

The Government of Costa Rica has issued a Tropical Storm Watch for
the Pacific coast from Santa Elena to Puntarenas.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Warning is in effect for...
* Limon Costa Rica to Bluefields Nicaragua

A Hurricane Watch is in effect for...
* North of Bluefields to Sandy Bay Sirpi Nicaragua
* South of Limon to the Costa Rica/Panama border

A Tropical Storm Warning is in effect for...
* North of Bluefields to Sandy Bay Sirpi Nicaragua
* Nargana Panama to Colon
* San Andres

A Tropical Storm Watch is in effect for...
* West of Colon Panama to the Costa Rica/Panama border
* Puntarenas Costa Rica to Puerto Sandino Nicaragua

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 Hurricane Watch means that hurricane conditions are possible
within the watch area, usually within 48 hours.

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 Nicaragua, Costa Rica, and Providencia Island
should monitor the progress of Otto.

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


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 400 AM EST (0900 UTC), the center of Hurricane Otto was located
near latitude 10.9 North, longitude 80.4 West. Otto is moving
toward the west-northwest near 5 mph (7 km/h), and this motion is
expected to continue today. A turn toward the west and an increase
in forward speed are expected tonight and Thursday. On the forecast
track, the center of Otto will move onshore within the hurricane
warning area on Thursday, and reach the Pacific coast of southern
Nicaragua or northern Costa Rica Thursday night or early Friday.

Maximum sustained winds are near 75 mph (120 km/h) with higher
gusts. Some strengthening is expected before Otto makes landfall
on Thursday, with weakening expected after the center moves inland.

Hurricane-force winds extend outward up to 10 miles (20 km) from the
center and tropical-storm-force winds extend outward up to 60 miles
(95 km).

The estimated minimum central pressure is 988 mb (29.18 inches).


HAZARDS AFFECTING LAND
----------------------
RAINFALL: Outer rain bands from Otto are expected to produce
rainfall accumulations of 4 to 8 inches over San Andres and
Providencia islands, and the higher terrain of central and western
Panama and southern Costa Rica through today. Total rainfall of 6
to 12 inches, with isolated amounts of 15 to 20 inches, can be
expected across northern Costa Rica and southern Nicaragua through
Thursday. These rains will likely result in life-threatening flash
floods and mud slides.

WIND: Hurricane conditions are expected within the hurricane
warning area on Thursday, with tropical storm conditions expected
to begin overnight tonight or Thursday morning, making outside
preparations difficult or dangerous. Hurricane conditions are
possible in the hurricane watch area on Thursday.

Tropical storm conditions are expected within warning area in
Nicaragua tonight and Thursday. Tropical storm conditions are
possible in the tropical storm watch area in Panama today and in San
Andres later today. Tropical storm conditions are possible in the
watch area along the Pacific coasts of Costa Rica and Nicaragua by
Thursday night.

STORM SURGE: The combination of a dangerous storm surge and large
and destructive waves could raise water levels by as much 2 to 4
feet above normal tide levels in areas of onshore flow within the
hurricane warning area.

SURF: Swells generated by Otto are likely to cause life-threatening
surf and rip current conditions over the next several days along the
coasts of Panama, Costa Rica, and Nicaragua. Please consult
products from your local weather office.


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

$$
Forecaster Brennan

[arlwx]

HURRICANE OTTO DISCUSSION NUMBER 10
NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016
400 AM EST WED NOV 23 2016

The satellite presentation of Otto has not changed much overnight,
as deep convection continues to burst near the estimated center
position in a small ragged CDO pattern. The latest Dvorak estimates
are T4.0/65 kt from TAFB and SAB, and that will be the intensity
for this advisory. An Air Force Reserve Hurricane Hunter aircraft
is already en route to investigate Otto later this morning.

Vertical shear, currently analyzed at 15-20 kt, should lessen a
little bit in the next 12 to 24 h, but given the ragged nature of
the system right now, only modest strengthening is expected before
landfall. Weakening is then forecast through 48 hours while the
center moves across Central America. Once Otto reaches the eastern
Pacific, gradual weakening is expected to continue due to increasing
shear and a drier atmospheric environment. In fact, the 00Z GFS
and UKMET model runs both show the circulation of Otto dissipating
in 4-5 days, and the NHC forecast now shows a remnant low by the end
of the period. The new NHC intensity forecast is close to the
SHIPS model through 72 hours and follows the weakening trend of the
global models after that time.

Otto is moving toward the west-northwest with an initial motion
estimate of 290/04, although it has been difficult to pinpoint the
center overnight. The mid-level ridge currently centered north of
Otto will build westward and amplify during the forecast period.
As a result, Otto should turn westward and accelerate in the short
term, bringing the center to the coast in about 36 hours. Later in
the period, a motion south of due west is indicated as the mid-level
ridge amplifies over the eastern Pacific. The latest official
forecast is slightly north of and slower than the previous one
through landfall, and then has been adjusted southward and faster
late in the period. The new NHC track is closest to the FSU
Superensemble through 72 hours and is near a blend of the ECMWF
and GFS after that time.

Based on the latest forecast, tropical storm watches have been
issued for portions of the Pacific coasts of Nicaragua and Costa
Rica.

FORECAST POSITIONS AND MAX WINDS

INIT 23/0900Z 10.9N 80.4W 65 KT 75 MPH
12H 23/1800Z 11.1N 81.2W 65 KT 75 MPH
24H 24/0600Z 11.2N 82.3W 70 KT 80 MPH
36H 24/1800Z 11.3N 83.9W 65 KT 75 MPH...INLAND
48H 25/0600Z 11.0N 86.0W 45 KT 50 MPH...OVER WATER
72H 26/0600Z 10.0N 91.0W 40 KT 45 MPH
96H 27/0600Z 9.5N 96.0W 35 KT 40 MPH
120H 28/0600Z 10.0N 100.0W 30 KT 35 MPH...POST-TROP/REMNT LOW

$$
Forecaster Brennan

[NotoSans]

Looks like a 50-knot tropical storm right now based on latest recon.

[TheEuropean]

Looks like a 50-knot tropical storm right now based on latest recon.

Right, seems to be much weaker than yesterday.

[TheEuropean]

NHC downgraded Otto, but to a 60-knot storm:

BULLETIN
TROPICAL STORM OTTO INTERMEDIATE ADVISORY NUMBER 10A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016
700 AM EST WED NOV 23 2016

...AIR FORCE PLANE FINDS OTTO A LITTLE WEAKER...

SUMMARY OF 700 AM EST...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...11.0N 80.5W
ABOUT 185 MI...300 KM ENE OF LIMON COSTA RICA
ABOUT 235 MI...375 KM ESE OF BLUEFIELDS NICARAGUA
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 5 MPH...7 KM/H
MINIMUM CENTRAL PRESSURE...994 MB...29.35 INCHES

[TheEuropean]

It was a short mission, but recon measured up to 60 kt at flight level, so 60 kt is ok, I think.

000
URNT12 KNHC 231222
VORTEX DATA MESSAGE AL162016
A. 23/11:48:10Z
B. 10 deg 59 min N
080 deg 22 min W
C. 700 mb 3058 m
D. 44 kt
E. 155 deg 18 nm
F. 207 deg 41 kt
G. 140 deg 38 nm
H. 995 mb
I. 10 C / 3056 m
J. 16 C / 3042 m
K. 4 C / NA
L. NA
M. NA
N. 1345 / 7
O. 0.02 / 2 nm
P. AF301 0416A OTTO OB 16
MAX OUTBOUND AND MAX FL WIND 68 KT 309 / 18 NM 11:53:30Z
CNTR DROPSONDE SFC WIND 185 / 13 KT

[cycloneye]

TROPICAL STORM OTTO DISCUSSION NUMBER 11
NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016
1000 AM EST WED NOV 23 2016

Otto has lost some organization since yesterday. The last Air
Force Reserve reconnaissance mission reported that the eyewall has
dissipated, along with a 6-mb rise in pressure. Still, the maximum
700-mb flight-level winds were 68 kt, with SFMR winds of about 50
kt. The initial intensity is conservatively reduced to 60 kt for
this advisory.

It appears that the southeasterly shear has been a little stronger
than forecast yesterday, which has allowed some drier air to mix
into the cyclone. This is evident in the inner-core data from the
Air Force mission, which showed rather low dewpoints at 700 mb. The
global models are suggesting the shear will decrease before
landfall, and Otto should be moving over warmer waters later today
that have not be subjected to any storm-forced upwelling. These
factors suggest some restrengthening is possible overnight and
Thursday, which is consistent with the bulk of the guidance models.
Stronger shear over the eastern Pacific is expected to cause gradual
weakening of Otto in that basin, with remnant low status likely by
day 5. The official intensity forecast has been reduced somewhat
from the last one but still calls for Otto to be a hurricane at
landfall.

Aircraft fixes show that Otto continues to move toward the
west-northwest at 4 kt. A building mid-level ridge to the north of
Otto should cause the tropical cyclone to turn westward and
accelerate tonight. Late in the period, a motion south of due west
is indicated as the mid-level ridge amplifies over the eastern
Pacific. Model guidance is tightly clustered on this solution, and
the latest official forecast is very close to the previous one.



FORECAST POSITIONS AND MAX WINDS

INIT 23/1500Z 11.1N 80.7W 60 KT 70 MPH
12H 24/0000Z 11.2N 81.5W 60 KT 70 MPH
24H 24/1200Z 11.3N 83.0W 65 KT 75 MPH
36H 25/0000Z 11.2N 84.7W 45 KT 50 MPH...INLAND
48H 25/1200Z 10.8N 87.0W 40 KT 45 MPH...OVER WATER
72H 26/1200Z 10.0N 92.0W 35 KT 40 MPH
96H 27/1200Z 9.5N 97.0W 30 KT 35 MPH
120H 28/1200Z 10.0N 102.0W 25 KT 30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Blake

[Sanibel]

Hard to say why it weakened but the southern flow has to come up across the Central American mountain range. I suppose shear doesn't help with that restricted breathing room. I climbed Vulcan Baru in that area in 2000. Great country to visit despite having all our stuff stripped off us, including passports, by some locals with knives.

[cycloneye]

TROPICAL STORM OTTO DISCUSSION NUMBER 12
NWS NATIONAL HURRICANE CENTER MIAMI FL AL162016
400 PM EST WED NOV 23 2016

There has not been much overall change to the Otto's satellite
presentation today. While the convection temporarily weakened
this morning, thunderstorm activity has rebuilt near the center
during the afternoon. Satellite intensity estimates range from 55
to 65 kt, so the initial wind speed will remain 60 kt. An Air Force
Reserve Reconnaissance aircraft should be in Otto this evening to
obtain a better estimate.

The GFS and the ECMWF models continue to insist that shear near Otto
should decrease this evening and tomorrow due to the nearby
upper-level flow changing to a more easterly direction. Thus Otto
still has the chance to become a hurricane again before landfall on
Thursday, and the official forecast reflects this scenario. Otto
should abruptly weaken after landfall, with a more gradual weakening
anticipated over the eastern Pacific due to increasing easterly
shear. The intensity guidance is showing a slower demise of Otto at
long range, so the intensity forecast has been boosted slightly from
the previous one at days 3 and 4.

Otto is finally on the move, with the latest satellite fixes
indicating a westward motion at about 6 kt. A strengthening
mid-level ridge to the north of Otto should force the storm to move
a bit faster to the west on Thursday, with an even faster
south-of-west motion forecast over the weekend. Very few changes
were required to the track prediction on this advisory since the
model guidance remains in very good agreement.


FORECAST POSITIONS AND MAX WINDS

INIT 23/2100Z 11.2N 81.3W 60 KT 70 MPH
12H 24/0600Z 11.3N 82.3W 60 KT 70 MPH
24H 24/1800Z 11.2N 83.8W 65 KT 75 MPH
36H 25/0600Z 10.9N 85.8W 45 KT 50 MPH...INLAND
48H 25/1800Z 10.5N 88.0W 40 KT 45 MPH...OVER WATER
72H 26/1800Z 9.5N 92.5W 40 KT 45 MPH
96H 27/1800Z 9.5N 97.5W 35 KT 40 MPH
120H 28/1800Z 10.5N 102.5W 25 KT 30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Blake

[Macrocane]

Convection has been intensifyng and CDO has been expanding in the last few hours.

[Alyono]

VDM has the center dropsonde measuring 66 kt surface winds

[Alyono]

explosive intensification underway

cat 2/3 as per recon

[bahamaswx]

I'm impressed.

[Alyono]

233430 1102N 08134W 8440 01475 //// +182 //// 232032 034 037 003 01
233500 1103N 08135W 8414 01493 //// +180 //// 237030 034 039 003 01
233530 1104N 08136W 8439 01463 9966 +193 +188 227029 034 039 002 01
233600 1105N 08137W 8437 01458 9950 +202 +189 224034 038 043 004 00
233630 1106N 08138W 8422 01457 9939 +204 +190 216037 039 050 006 00
233700 1108N 08139W 8428 01434 9922 +199 +195 201039 041 052 006 00
233730 1109N 08141W 8416 01424 9905 +194 //// 195046 053 059 010 05
233800 1110N 08142W 8408 01413 9859 +222 +189 189049 054 /// /// 03
233830 1111N 08143W 8348 01442 9830 +219 +187 167042 057 059 008 03
233900 1113N 08145W 8395 01368 9824 +190 //// 111055 066 053 008 05
233930 1113N 08147W 8420 01353 9832 +192 //// 065076 085 088 016 01
234000 1113N 08149W 8449 01351 //// +190 //// 040092 095 092 015 05
234030 1112N 08151W 8421 01403 //// +184 //// 015098 103 /// /// 05
234100 1109N 08152W 8425 01429 9930 +184 //// 353090 102 095 050 05
234130 1107N 08152W 8411 01446 9951 +186 +186 344087 090 075 047 03
234200 1104N 08152W 8428 01454 9977 +178 //// 329077 084 063 034 05
234230 1102N 08152W 8408 01487 9971 +178 +174 325067 076 060 008 00
234300 1100N 08152W 8421 01484 //// +172 //// 324068 069 050 002 05
234330 1058N 08151W 8347 01560 //// +166 //// 319059 068 /// /// 05
234400 1058N 08149W 8051 01869 9972 +165 +158 306049 055 /// /// 05
234430 1059N 08148W 7805 02131 9960 +165 +135 295044 047 045 002 00
234500 1100N 08146W 7575 02381 9954 +152 +121 290040 045 045 002 00
234530 1101N 08145W 7347 02630 9939 +139 +114 269034 037 052 005 00
234600 1103N 08144W 7173 02829 9917 +143 +097 244037 042 058 008 03
234630 1105N 08144W 7062 02945 9895 +140 +092 212041 049 066 016 03
234700 1107N 08145W 6994 03013 9848 +165 +079 210045 055 068 015 03

[cycloneye]

...OTTO REGAINS HURRICANE STRENGTH...


SUMMARY OF 700 PM EST...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...11.2N 81.8W
ABOUT 140 MI...230 KM NE OF LIMON COSTA RICA
ABOUT 180 MI...285 KM ESE OF BLUEFIELDS NICARAGUA
MAXIMUM SUSTAINED WINDS...75 MPH...110 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...984 MB...29.06 INCHES