ATL: WILFRED - Advisories

[cycloneye]

BULLETIN
Tropical Storm Wilfred Advisory Number 1
NWS National Hurricane Center Miami FL AL232020
1100 AM AST Fri Sep 18 2020

...WILFRED FORMS IN THE EASTERN TROPICAL ATLANTIC...
...GET OUT THE GREEK ALPHABET FOR THE REST OF 2020...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...11.9N 32.4W
ABOUT 630 MI...1015 KM WSW OF THE CABO VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 1100 AM AST (1500 UTC), the center of Tropical Storm Wilfred was
located near latitude 11.9 North, longitude 32.4 West. Wilfred is
moving toward the west-northwest near 17 mph (28 km/h) and this
general motion is expected for the next few days.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Some slight strengthening is possible today, and weakening should
start this weekend and continue into next week.

Tropical-storm-force winds extend outward up to 140 miles (220 km)
from the center.

The estimated minimum central pressure is 1008 mb (29.77 inches).


HAZARDS AFFECTING LAND
----------------------
None


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

$$
Forecaster Blake


Tropical Storm Wilfred Discussion Number 1
NWS National Hurricane Center Miami FL AL232020
1100 AM AST Fri Sep 18 2020

Satellite images indicate that the broad area of low pressure over
the eastern Atlantic has become better-defined this morning. In
addition, scatterometer data also show a closed circulation, albeit
with some rain contamination causing some noise near the center.
The initial wind speed is set to 35 kt, in accordance with
scatterometer data from last night (this morning's data missed the
eastern side of the storm). Thus Wilfred has formed, continuing
the record-setting pace of the 2020 hurricane season since it is
the earliest 21st named storm on record, about 3 weeks earlier
than Vince of 2005.

Further intensification is possible during the next day or two
before a large upper-level trough is forecast to drop into the
path of the storm and stay there for at least a few days. That
should promote weakening due to a substantial increase in shear, and
most of the global models show this tropical cyclone opening up
into a trough by day 5. The official forecast follows this
scenario, and the NHC intensity forecast is a blend of the
consensus and corrected-consensus aids.

Wilfred is moving west-northwestward at about 15 kt. The storm
is forecast to continue this motion for the next several days,
owing to steering from the low- to middle-level subtropical ridge.
The guidance is in fair agreement, and the official forecast is
near or west of the consensus at all times, leaning in the
direction of the HCCA corrected-consensus. I should mention that
if Wilfred intensifies more than expected, it would probably move a
bit right of the forecast track for a while due to the expected
southwesterly flow at higher levels, before eventually turning back
west-northwestward.

FORECAST POSITIONS AND MAX WINDS

INIT 18/1500Z 11.9N 32.4W 35 KT 40 MPH
12H 19/0000Z 12.6N 34.6W 40 KT 45 MPH
24H 19/1200Z 13.5N 37.5W 40 KT 45 MPH
36H 20/0000Z 14.5N 40.2W 40 KT 45 MPH
48H 20/1200Z 15.6N 42.8W 35 KT 40 MPH
60H 21/0000Z 16.7N 45.5W 30 KT 35 MPH
72H 21/1200Z 17.3N 47.5W 30 KT 35 MPH
96H 22/1200Z 18.0N 50.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 23/1200Z...DISSIPATED

$$
Forecaster Blake

[cycloneye]

BULLETIN
Tropical Storm Wilfred Advisory Number 2
NWS National Hurricane Center Miami FL AL232020
500 PM AST Fri Sep 18 2020

...WILFRED COULD STRENGTHEN OVERNIGHT...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...12.5N 34.4W
ABOUT 735 MI...1185 KM WSW OF THE CABO VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 18 MPH...30 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 500 PM AST (2100 UTC), the center of Tropical Storm Wilfred was
located near latitude 12.5 North, longitude 34.4 West. Wilfred is
moving toward the west-northwest near 18 mph (30 km/h), and this
general motion is expected to continue for the next few days.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Wilfred could strengthen a little overnight and Saturday before
weakening likely begins by Sunday.

Tropical-storm-force winds extend outward up to 140 miles (220 km)
from the center.

The estimated minimum central pressure is 1008 mb (29.77 inches).


HAZARDS AFFECTING LAND
----------------------
None


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

$$
Forecaster Blake



Tropical Storm Wilfred Discussion Number 2
NWS National Hurricane Center Miami FL AL232020
500 PM AST Fri Sep 18 2020

There haven't been a lot of changes with Wilfred today, with the
northern side of the circulation looking rather dry while the
center remains close to a burst of convection. The initial wind
speed is kept 35 kt, closest to the TAFB classification. Wilfred
could strengthen some during the next day or so before increasing
upper-level westerlies winds likely begin by Sunday. A gradual
weakening is expected into early next week, though the model
guidance is in worse agreement than the last advisory due to the
positioning of an upper-level low. The forecast continues to
show the storm ending up on the convergent side of the low and
dissipating, close to the previous one.

Wilfred is moving west-northwestward at about 16 kt, after
accounting for a re-positioning westward. Most of the guidance
agrees on a scenario that maintains this track for the next few
days, with a turn toward the west as the cyclones dissipates. The
new forecast is closest to the GFS-based guidance. Similar to the
intensity forecast, however, there are some models that suggest
Wilfred could slow down and turn to the right in a couple of days if
it is stronger than anticipated.

FORECAST POSITIONS AND MAX WINDS

INIT 18/2100Z 12.5N 34.4W 35 KT 40 MPH
12H 19/0600Z 13.2N 36.7W 40 KT 45 MPH
24H 19/1800Z 14.3N 39.7W 40 KT 45 MPH
36H 20/0600Z 15.4N 42.6W 40 KT 45 MPH
48H 20/1800Z 16.4N 45.4W 35 KT 40 MPH
60H 21/0600Z 17.1N 48.0W 30 KT 35 MPH
72H 21/1800Z 17.5N 50.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 22/1800Z...DISSIPATED

$$
Forecaster Blake

[cycloneye]

BULLETIN
Tropical Storm Wilfred Advisory Number 3
NWS National Hurricane Center Miami FL AL232020
1100 PM AST Fri Sep 18 2020

...POORLY ORGANIZED WILFRED STILL A STORM...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...12.8N 36.0W
ABOUT 830 MI...1340 KM WSW OF THE CABO VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 18 MPH...30 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 1100 PM AST (0300 UTC), the center of Tropical Storm Wilfred was
located near latitude 12.8 North, longitude 36.0 West. Wilfred is
moving toward the west-northwest near 18 mph (30 km/h), and this
general motion is expected to continue for the next few days.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Some slight strengthening is possible Saturday before weakening
likely begins by Sunday.

Tropical-storm-force winds extend outward up to 140 miles (220 km)
from the center.

The estimated minimum central pressure is 1008 mb (29.77 inches).


HAZARDS AFFECTING LAND
----------------------
None


NEXT ADVISORY
-------------
Next complete advisory at 500 AM AST.

$$
Forecaster Roberts



Tropical Storm Wilfred Discussion Number 3
NWS National Hurricane Center Miami FL AL232020
1100 PM AST Fri Sep 18 2020

Conventional satellite imagery shows that Wilfred's surface
circulation has lost quite a bit of definition during the last
several hours, and it has been difficult to pinpoint the center.
Additionally, deep convection has become less organized and the
cloud tops just to the east of the estimated center position have
warmed considerably. The initial intensity is generously held at
35 kt for this advisory and is in best agreement with blend of the
subjective and objective satellite intensity estimates.

The GFS and ECMWF global model soundings indicate 30-35 kt of
northeasterly shear at about 300 mb, and it's apparently
undercutting the much lighter, diffluent southeasterly flow above.
Statistical-dynamical guidance, however, still show an outside
chance of some strengthening Saturday, and the NHC forecast follows
suit. Afterward, a combination of Teddy's massive outflow and
increasing northwesterly shear produced by an mid- to upper-level
trough to the north of the cyclone, should induce slow weakening on
Sunday and this trend should continue through the forecast period.

The initial motion is estimated to be west-northwestward, or
285/16 kt, and the cyclone is being steered by a low to
mid-tropospheric subtropical ridge to the north. A few of the
global models are hinting at a slow turn toward the north-northwest
prior to dissipation as the steering pattern becomes very meridional
with developing high amplitude high pressure over the eastern
Atlantic, and Hurricane Teddy well to the northwest creating a large
weakness over the western Atlantic. For now, the NHC forecast shows
some reduction in forward speed at day 3, before dissipation, and
lies close to the consensus aids, HCCA and TVCA.


FORECAST POSITIONS AND MAX WINDS

INIT 19/0300Z 12.8N 36.0W 35 KT 40 MPH
12H 19/1200Z 13.5N 38.3W 40 KT 45 MPH
24H 20/0000Z 14.5N 40.9W 40 KT 45 MPH
36H 20/1200Z 15.8N 43.8W 35 KT 40 MPH
48H 21/0000Z 16.7N 46.3W 35 KT 40 MPH
60H 21/1200Z 17.3N 48.3W 30 KT 35 MPH
72H 22/0000Z 17.9N 50.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 23/0000Z...DISSIPATED

$$
Forecaster Roberts

[cycloneye]

BULLETIN
Tropical Storm Wilfred Advisory Number 4
NWS National Hurricane Center Miami FL AL232020
500 AM AST Sat Sep 19 2020

...WOEFUL WILFRED HEADING WEST-NORTHWESTWARD...


SUMMARY OF 500 AM AST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...13.1N 36.9W
ABOUT 885 MI...1425 KM W OF THE CABO VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 500 AM AST (0900 UTC), the center of Tropical Storm Wilfred was
located near latitude 13.1 North, longitude 36.9 West. Wilfred is
moving toward the west-northwest near 17 mph (28 km/h), and this
general motion is expected to continue for the next few days.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Small fluctuations in intensity are possible over the weekend. A
general weakening trend should begin by late Sunday and Wilfred is
forecast to become a remnant low in a few days.

Tropical-storm-force winds extend outward up to 105 miles (165 km)
from the center.

The estimated minimum central pressure is 1007 mb (29.74 inches).


HAZARDS AFFECTING LAND
----------------------
None


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

$$
Forecaster Zelinsky



Tropical Storm Wilfred Discussion Number 4
NWS National Hurricane Center Miami FL AL232020
500 AM AST Sat Sep 19 2020

Helpful AMSR microwave imagery from near 4Z revealed that Wilfred
consists of a small low embedded within a broader elongated
area of low pressure. A skinny, ragged band of convection wraps
around the western and southern portions of the tropical storm, but
Wilfred is only producing a small amount of convection near its
center. Objective and subjective satellite intensity estimates are
generally near 35 kt, and the intensity is held at that value.

No noteworthy changes were made to the NHC track or intensity
forecasts. Wilfred should continue to move generally
west-northwestward for the next few days, steered by a
subtropical ridge to the north. Small fluctuations in intensity are
possible for the next day or two, but Wilfred should be on the
overall decline by the end of the weekend due to increasing wind
shear and an expected influx of dry, stable air. The dynamical
guidance consensus is that Wilfred will open into a trough and
dissipate in about 72 h, and this is reflected in the NHC forecast.
Both the NHC track and intensity forecasts are based on the
multi-model consensus throughout the forecast period.


FORECAST POSITIONS AND MAX WINDS

INIT 19/0900Z 13.1N 36.9W 35 KT 40 MPH
12H 19/1800Z 13.8N 39.0W 40 KT 45 MPH
24H 20/0600Z 14.8N 41.7W 35 KT 40 MPH
36H 20/1800Z 15.8N 44.4W 35 KT 40 MPH
48H 21/0600Z 16.5N 46.8W 30 KT 35 MPH
60H 21/1800Z 16.8N 48.6W 30 KT 35 MPH...POST-TROP/REMNT LOW
72H 22/0600Z...DISSIPATED

$$
Forecaster Zelinsky

[cycloneye]

BULLETIN
Tropical Storm Wilfred Advisory Number 5...Corrected
NWS National Hurricane Center Miami FL AL232020
1100 AM AST Sat Sep 19 2020

Corrected headline

...WILFRED MOVING WEST-NORTHWESTWARD ACROSS THE TROPICAL ATLANTIC
WITH LITTLE CHANGE IN STRENGTH...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...13.4N 38.1W
ABOUT 960 MI...1540 KM W OF THE CABO VERDE ISLANDS
ABOUT 1555 MI...2505 KM E OF THE LESSER ANTILLES
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 1100 AM AST (1500 UTC), the center of Tropical Storm Wilfred was
located near latitude 13.4 North, longitude 38.1 West. Wilfred is
moving toward the west-northwest near 14 mph (22 km/h), and this
general motion is expected to continue for the next few days.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Little change in intensity is expected for the next day or so,
followed by gradual weakening on Monday. Wilfred is expected to
become a remnant low by Monday night and dissipate on Tuesday.

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

The estimated minimum central pressure is 1007 mb (29.74 inches).


HAZARDS AFFECTING LAND
----------------------
None


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

$$
Forecaster Brennan


Tropical Storm Wilfred Discussion Number 5
NWS National Hurricane Center Miami FL AL232020
1100 AM AST Sat Sep 19 2020

Wilfred still consists of a very small low-level circulation
embedded within an elongated area of low pressure. There has been a
bit of an increase in deep convection near/over the estimated center
during the past few hours, and the intensity remains 35 kt based on
the latest Dvorak classifications from TAFB and SAB and UW-CIMSS
SATCON.

Wilfred will be moving over SSTs of around 28C but will experience a
gradual increase in westerly shear during the next 24 to 36 hours as
an upper-level trough amplifies to the northwest, and this should
result in little change in strength during that time. Beyond that
time, the cyclone moves into a drier and more stable airmass, which
should result in the system becoming a remnant low and dissipating
in 60 to 72 hours. The new NHC intensity forecast is close to the
latest IVCN consensus.

The initial motion estimate based on the latest satellite fixes
is 285/12. Wilfred should continue moving generally west-
northwestward for the next 24 to 36 hours and then turn more
westward by 48 h as it becomes a shallower system. The new NHC
track forecast is a bit faster than the previous one and has
been adjusted farther south at 36 h and beyond, trending toward
the latest consensus aids.

FORECAST POSITIONS AND MAX WINDS

INIT 19/1500Z 13.4N 38.1W 35 KT 40 MPH
12H 20/0000Z 14.2N 40.2W 35 KT 40 MPH
24H 20/1200Z 15.2N 43.1W 35 KT 40 MPH
36H 21/0000Z 15.9N 45.8W 35 KT 40 MPH
48H 21/1200Z 16.2N 48.0W 30 KT 35 MPH
60H 22/0000Z 16.3N 49.8W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 22/1200Z...DISSIPATED

$$
Forecaster Brennan

[cycloneye]

BULLETIN
Tropical Storm Wilfred Advisory Number 6
NWS National Hurricane Center Miami FL AL232020
500 PM AST Sat Sep 19 2020

...TINY WILFRED MOVING WEST-NORTHWESTWARD...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...14.0N 39.2W
ABOUT 1025 MI...1645 KM W OF THE CABO VERDE ISLANDS
ABOUT 1480 MI...2380 KM E OF THE LESSER ANTILLES
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 500 PM AST (2100 UTC), the center of Tropical Storm Wilfred was
located near latitude 14.0 North, longitude 39.2 West. Wilfred is
moving toward the west-northwest near 14 mph (22 km/h), and this
general motion is expected to continue through Sunday, followed by
a westward motion late Sunday and Monday.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Little change in strength is expected during the next day or so.
Weakening is expected on Monday, and Wilfred is expected to
dissipate by Tuesday.

Tropical-storm-force winds extend outward up to 45 miles (75 km)
from the center.

The estimated minimum central pressure is 1007 mb (29.74 inches).


HAZARDS AFFECTING LAND
----------------------
None


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

$$
Forecaster Brennan


Tropical Storm Wilfred Discussion Number 6
NWS National Hurricane Center Miami FL AL232020
500 PM AST Sat Sep 19 2020

A small low-level swirl that is apparently Wilfred's circulation
center was noted in late afternoon visible imagery. The coldest
cloud tops are in a small area of bursting convection to the
northeast of the center with a ragged convective band noted to
the south and southwest. The latest objective and subjective
satellite intensity estimates remain 35 kt, and that will be the
intensity for this advisory, but could be a bit generous.

Increasing westerly shear and a drying airmass along the forecast
track should result in weakening within 36 to 48 hours, and global
models show the cyclone dissipating by 60 h. However, given the
small size of the system, it wouldn't be surprising if the cyclone
weakened or dissipated sooner than shown here.

The initial motion estimate is 290/12. Wilfred should continue
west-northwestward for the next 24 to 36 hours before turning
westward in the low-level flow prior to dissipation. The new NHC
track forecast is close to the previous one and lies near the
consensus aids and the middle of the guidance envelope.

FORECAST POSITIONS AND MAX WINDS

INIT 19/2100Z 14.0N 39.2W 35 KT 40 MPH
12H 20/0600Z 14.8N 41.3W 35 KT 40 MPH
24H 20/1800Z 15.6N 44.0W 35 KT 40 MPH
36H 21/0600Z 16.0N 46.6W 35 KT 40 MPH
48H 21/1800Z 16.2N 48.6W 30 KT 35 MPH
60H 22/0600Z...DISSIPATED

$$
Forecaster Brennan

[cycloneye]

BULLETIN
Tropical Storm Wilfred Advisory Number 7
NWS National Hurricane Center Miami FL AL232020
1100 PM AST Sat Sep 19 2020

...WILFRED CONTINUES WEST-NORTHWESTWARD WITH NO CHANGE IN
STRENGTH...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...14.5N 40.5W
ABOUT 1105 MI...1775 KM W OF THE CABO VERDE ISLANDS
ABOUT 1390 MI...2235 KM E OF THE LESSER ANTILLES
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 1100 PM AST (0300 UTC), the center of Tropical Storm Wilfred was
located near latitude 14.5 North, longitude 40.5 West. Wilfred is
moving toward the west-northwest near 16 mph (26 km/h), and this
general motion is expected to continue through Sunday, followed by
a slower westward motion late Sunday and Monday.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Little change in strength is expected through Sunday. Gradual
Weakening is expected Sunday night and Monday, and Wilfred is
expected to dissipate by Tuesday.

Tropical-storm-force winds extend outward up to 45 miles (75 km)
from the center.

The estimated minimum central pressure is 1007 mb (29.74 inches).


HAZARDS AFFECTING LAND
----------------------
None


NEXT ADVISORY
-------------
Next complete advisory at 500 AM AST.

$$
Forecaster Brown


Tropical Storm Wilfred Discussion Number 7
NWS National Hurricane Center Miami FL AL232020
1100 PM AST Sat Sep 19 2020

Microwave data since the previous advisory indicates that the
center of Wilfred is located near the southwestern edge of the deep
convection. The displacement of the center from the convection
is the result of moderate westerly vertical wind shear. The
initial intensity remains 35 kt, and is based on an ASCAT-B
overpass from around 0000 UTC that revealed peak winds of 30-35 kt.

Wilfred is headed toward an area of increasing westerly wind shear,
and a drier mid-level environment. These negative factors should
lead to weakening in 24 to 48 h, and the global models dissipate
the cyclone within the next few days. The official forecast
follows suit, but given the small size of the cyclone it could
weaken and dissipate sooner than indicated below.

The initial motion estimate is 295/14, a little faster than before.
Wilfred is forecast to remain on a west-northwestward heading
through Sunday, but should turn westward within the low-level flow
by Sunday night or Monday. The latest NHC track forecast is once
again similar to the previous advisory and near the middle of the
guidance envelope.

FORECAST POSITIONS AND MAX WINDS

INIT 20/0300Z 14.5N 40.5W 35 KT 40 MPH
12H 20/1200Z 15.3N 42.6W 35 KT 40 MPH
24H 21/0000Z 15.8N 45.2W 35 KT 40 MPH
36H 21/1200Z 16.2N 47.3W 30 KT 35 MPH
48H 22/0000Z 16.4N 49.2W 25 KT 30 MPH
60H 22/1200Z...DISSIPATED

$$
Forecaster Brown

[cycloneye]

BULLETIN
Tropical Storm Wilfred Advisory Number 8
NWS National Hurricane Center Miami FL AL232020
500 AM AST Sun Sep 20 2020

...WILFRED WILTING IN THE FACE OF HOSTILE ENVIRONMENTAL
CONDITIONS...


SUMMARY OF 500 AM AST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...15.0N 42.0W
ABOUT 1200 MI...1930 KM W OF THE CABO VERDE ISLANDS
ABOUT 1285 MI...2070 KM E OF THE LESSER ANTILLES
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 500 AM AST (0900 UTC), the center of Tropical Storm Wilfred was
located near latitude 15.0 North, longitude 42.0 West. Wilfred is
moving toward the west-northwest near 16 mph (26 km/h). A turn
toward the west with a slight decrease in forward speed is expected
by tonight.

Maximum sustained winds are near 40 mph (65 km/h) with higher gusts.
Weakening is anticipated. Wilfred is not expected to last more than
another couple of days and could dissipate as soon as later today.

Tropical-storm-force winds extend outward up to 45 miles (75 km)
from the center.

The estimated minimum central pressure is 1007 mb (29.74 inches).


HAZARDS AFFECTING LAND
----------------------
None


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

$$
Forecaster Zelinsky


Tropical Storm Wilfred Discussion Number 8
NWS National Hurricane Center Miami FL AL232020
500 AM AST Sun Sep 20 2020

It is unclear if Wilfred still exists, and if so, exactly where it
is located. Although there is clear evidence of a broad elongated
circulation, the formerly small center of Wilfred is either
obscured by higher clouds or has dissipated. AMSR-2 microwave
imagery at 0431 UTC showed only evidence of a northwest-southeast
oriented trough with one or more embedded mesoscale lows. Visible
imagery and the next round of ASCAT passes will hopefully provide
more information about Wilfred's status later this morning. The
intensity remains 35 kt based on ASCAT data from last night, but
more recent Dvorak estimates are lower.

Due to the uncertainty associated with Wilfred's status and
location, the motion estimate is a very uncertain 295/15 kt. In
general, Wilfred or its eventual remnants should continue on a
west-northwestward heading today, and then could turn westward by
early Monday. The NHC forecast is very similar to the previous one
and lies near the middle of the guidance suite.

Virtually no change has been made to the official intensity
forecast. Wilfred will likely gradually weaken until it dissipates
due to a combination of increasing wind shear and a dry
environment. The exact point at which Wilfred will become a trough
varies from model to model, but confidence is fairly high that
Wilfred won't last much longer than another day or two. The NHC
forecast carries Wilfred for 48 h based on persistence from the
previous advisory, but if recent trends hold, it could dissipate as
soon as later today.


FORECAST POSITIONS AND MAX WINDS

INIT 20/0900Z 15.0N 42.0W 35 KT 40 MPH
12H 20/1800Z 15.7N 44.1W 35 KT 40 MPH
24H 21/0600Z 16.2N 46.5W 30 KT 35 MPH
36H 21/1800Z 16.5N 48.5W 30 KT 35 MPH
48H 22/0600Z 16.7N 50.3W 25 KT 30 MPH
60H 22/1800Z...DISSIPATED

$$
Forecaster Zelinsky

[cycloneye]

BULLETIN
Tropical Depression Wilfred Advisory Number 9
NWS National Hurricane Center Miami FL AL232020
1100 AM AST Sun Sep 20 2020

...WILFRED WEAKENS TO A TROPICAL DEPRESSION OVER THE OPEN
ATLANTIC...


SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...15.7N 44.2W
ABOUT 1340 MI...2160 KM W OF THE CABO VERDE ISLANDS
ABOUT 1135 MI...1830 KM E OF THE LESSER ANTILLES
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 20 MPH...31 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 1100 AM AST (1500 UTC), the center of Tropical Depression Wilfred
was located near latitude 15.7 North, longitude 44.2 West. The
depression is moving toward the west-northwest near 20 mph (31
km/h). Wilfred should slow its forward speed while heading toward
the west or west-northwestward for the next few days until
dissipation.

Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Wilfred should weaken to a remnant low within a couple days.

The estimated minimum central pressure is 1008 mb (29.77 inches).


HAZARDS AFFECTING LAND
----------------------
None


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

$$
Forecaster Landsea



Tropical Depression Wilfred Discussion Number 9
NWS National Hurricane Center Miami FL AL232020
1100 AM AST Sun Sep 20 2020

First-light visible imagery of Wilfred shows a well-defined center
south of widespread - but not very well banded - deep convection.
The improved positioning this morning allows for a more confident
assessment of its movement toward the west-northwest at 17 kt. As
the system slowly winds down, it will be increasingly steered by
the low-level flow indicating a slower movement toward the west or
west-northwest until dissipation. The new track forecast is
slightly farther west due to the faster initial motion within 36
hours, then slightly farther east afterward based upon the TVCN
track consensus approach.

While the ASCAT scatterometer passes this morning missed Wilfred's
center, ASCAT-B observed 30 kt peak winds in its northeastern
quadrant. This value is used as the initial intensity, consistent
with both SAB and TAFB's Dvorak classifications.

The combination of outflow from Hurricane Teddy as well as winds on
the southern side of an impinging upper-level trough are causing
about 20 kt vertical shear from the west-northwest. This shear
should increase over the next couple of days as Wilfred gets into
closer proximity with the trough. The strong shear and dry
mid-level humidities should continue to cause a reduction of the
deep convection and lead to the system becoming a remnant low in a
couple of days followed within another day or so by dissipation.
All statistical and dynamical intensity guidance is in agreement
with this scenario. Alternatively, Wilfred could become a remnant
low sooner, if the convection ceases later today or Monday.

FORECAST POSITIONS AND MAX WINDS

INIT 20/1500Z 15.7N 44.2W 30 KT 35 MPH
12H 21/0000Z 16.2N 46.3W 30 KT 35 MPH
24H 21/1200Z 16.5N 48.4W 25 KT 30 MPH
36H 22/0000Z 16.8N 50.0W 25 KT 30 MPH
48H 22/1200Z 17.0N 51.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
60H 23/0000Z 17.2N 52.7W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 23/1200Z...DISSIPATED

$$
Forecaster Landsea

[cycloneye]

BULLETIN
Tropical Depression Wilfred Advisory Number 10
NWS National Hurricane Center Miami FL AL232020
500 PM AST Sun Sep 20 2020

...WILFRED REMAINS A TROPICAL DEPRESSION OVER THE OPEN ATLANTIC...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...15.9N 45.8W
ABOUT 1445 MI...2330 KM W OF THE CABO VERDE ISLANDS
ABOUT 1030 MI...1660 KM E OF THE LESSER ANTILLES
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 20 MPH...31 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 500 PM AST (2100 UTC), the center of Tropical Depression Wilfred
was located near latitude 15.9 North, longitude 45.8 West. The
depression is moving toward the west-northwest near 20 mph (31
km/h). Wilfred should slow its forward speed while heading toward
the west or west-northwestward for the next couple days until
dissipation.

Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Wilfred should weaken to a remnant low within a day or two, but
could also degenerate into a trough of low pressure during that
time.

The estimated minimum central pressure is 1008 mb (29.77 inches).


HAZARDS AFFECTING LAND
----------------------
None


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

$$
Forecaster Landsea


Tropical Depression Wilfred Discussion Number 10
NWS National Hurricane Center Miami FL AL232020
500 PM AST Sun Sep 20 2020

Wilfred is not a healthy tropical cyclone as strong vertical shear
from the combination of outflow from Hurricane Teddy as well as
winds on the southern side of a nearby upper-level trough are
impinging upon the system. While there is substantial deep
convection, it is more linear rather than curved in appearance and
it may be more a product of forcing from the upper-level trough
rather than the tropical cyclone itself. Dvorak classifications
from SAB and TAFB have reduced some at 18Z, though the intensity
remains a perhaps generous 30 kt.

The tropical cyclone continues to move west-northwest at a fast 17
kt clip. As the system slowly winds down, it will be increasingly
steered by the low-level flow indicating a slower movement toward
the west or west-northwest until dissipation. The new track
forecast is similar to that from the previous advisory, except for
the final 60 hr point that does show a turn toward the northwest
based upon the TVCN and HCCA track consensus techniques.

Strong shear and dry mid-level humidities should continue to cause
a reduction in the deep convection and lead to the system becoming
a remnant low in a day or two followed shortly thereafter by
dissipation. Most statistical and dynamical intensity guidance is
in agreement. A plausible alternate scenario is that the small
circulation opens up into a trough and dissipation occurs sooner
than indicated below. It is worth noting that the ECMWF model does
suggest the possibility of reformation of the system farther north
by day three. However, this scenario is discounted at this time.

FORECAST POSITIONS AND MAX WINDS

INIT 20/2100Z 15.9N 45.8W 30 KT 35 MPH
12H 21/0600Z 16.3N 48.0W 30 KT 35 MPH
24H 21/1800Z 16.5N 49.9W 25 KT 30 MPH
36H 22/0600Z 16.5N 50.8W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 22/1800Z 16.8N 51.8W 20 KT 25 MPH...POST-TROP/REMNT LOW
60H 23/0600Z 17.8N 52.7W 20 KT 25 MPH...DISSIPATED
72H 23/1800Z...DISSIPATED

$$
Forecaster Landsea

[cycloneye]

BULLETIN
Remnants Of Wilfred Advisory Number 11
NWS National Hurricane Center Miami FL AL232020
1100 PM AST Sun Sep 20 2020

...WILFRED DEGENERATES INTO A TROUGH OF LOW PRESSURE...
...THIS IS THE LAST ADVISORY...


SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...15.9N 47.4W
ABOUT 1555 MI...2500 KM W OF THE CABO VERDE ISLANDS
ABOUT 925 MI...1490 KM E OF THE LESSER ANTILLES
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...W OR 275 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND OUTLOOK
----------------------
At 1100 PM AST (0300 UTC), the remnants of Wilfred were located near
latitude 15.9 North, longitude 47.4 West. The remnants are moving
toward the west near 17 mph (28 km/h), and this general motion
should continue during the next day or two.

Maximum sustained winds are near 35 mph (55 km/h) with higher
gusts. Winds should continue to decrease over the next couple of
days.

The estimated minimum central pressure is 1008 mb (29.77 inches).


HAZARDS AFFECTING LAND
----------------------
None


NEXT ADVISORY
-------------
This is the last public advisory issued by the National Hurricane
Center on Wilfred. Additional information on this system can be
found in High Seas Forecasts issued by the National Weather
Service, under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and
online at ocean.weather.gov/shtml/NFDHSFAT1.php

$$
Forecaster Brown