[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 142341
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Fri Dec 15 2023

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 31N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1800 UTC surface analysis and satellite imagery through
2330 UTC.

...SPECIAL FEATURES...

Central Atlantic Gale Warning: A 1003 mb low is located near
27N44W. Near gale to gale- force northeast to east winds along
with seas of 15 to 18 ft are occurring northwest of the low from
26N to 30N between 40W-46W. Near gale force to gale force winds
are also likely on the east side of the low from 24N to 29N
between 39W and 45W. Satellite imagery shows a band of scattered
moderate convection north of 17N between 34W and 44W. This
activity is shifting north- northeastward through this evening.
As it does, the tight pressure gradient producing the gales will
weaken just enough to allow for the gale-force winds to drop to
just below gale criteria. Seas will gradually subside through Fri
within the area of the low pressure system.

Atlantic Significant North Swell: Large north swell due to the
gale force low continues to sustain 12 to 15 ft seas from 21N to
31N between 38W and 51W. This swell will subside by tonight into
Fri morning west of 45W. Seas east of 45W and north of 25N will
remain elevated through Fri night due to ongoing near gale force
winds associated with the low pressure system mentioned above.

Western Atlantic and Florida Offshore Waters Gale Warning and
Significant Swell Event: A frontal boundary extends over the
northern Bahamas to the Florida Straits. An earlier ASCAT pass
shows a large swath of near gale- force northeast winds north of
the boundary and west of 68W. Gale force winds are likely
occurring over waters between the Bahamas and Florida from 26N to
30N. Seas within these areas of winds are 8 to 15 ft. The
prevailing tight pressure gradient between strong high pressure
over the eastern U.S. and lower pressures in the Gulf of Mexico
and NW Caribbean will support near gale force to gale force winds
offshore Florida through the weekend. Seas will build to 17 ft
between Florida and the Bahamas and 15 to 17 ft between 26N and
29N behind the front by Fri. Seas of 12 to 14 ft will spread
southward between 60W and the north facing coasts of the Bahamas,
reaching 22N by Sat morning. Seas will gradually subside through
the weekend.

Gulf of Mexico Gale Warning: Strong high pressure building over
the eastern U.S. is tightening the pressure gradient across the
Gulf of Mexico, supporting frequent gusts to gale- force offshore
of the Florida Panhandle. Winds will increase to gale force over
the NE Gulf tonight through Fri. Low pressure will form in the SW
Gulf by Fri night then move NE and into Florida Sat night through Sun.
This will cause additional gales in the NE Gulf. A cold front
will trail from the low, exiting the Gulf early on Sun. Expect
widespread showers and thunderstorms over most of the central and
eastern Gulf through early Sun. Seas with these winds are forecast
to be 10-15 ft. Winds diminish and seas subside by Sun morning.

For more details on the Significant Swell and Gale Warnings,
please read the latest High Seas Forecast issued by the National
Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml.

...MONSOON TROUGH/ITCZ...

The monsoon trough remains mainly inland over Africa. The ITCZ
begins near 05N11W to 05N30W to 03N50W. Scattered moderate
convection is noted from 00N to 08N between 10W and 41W.

...GULF OF MEXICO...

Please read the Special Features section for details on the Gale
Warning in the NE Gulf and a forming gale force low pressure
system occurring this weekend.

A stationary front related to the boundary in the western Atlantic
Gale force winds Special Feature, enters the Gulf of Mexico
through the Florida Straits to near 23N91W. A large swath of
strong to near gale force E winds is noted behind the boundary
with rough seas of 8 to 15 ft. West of 92W, fresh to strong E
winds with 7 to 12 ft seas are noted. A surface trough is
depicted in the SW Gulf. Fresh NE winds shifting NW south of 20N
surround the feature. Broken to overcast multilayered clouds along
with scattered to numerous showers and areas of moderate rain are
over the basin north of 23N.

For the forecast, strong high pressure building across the
eastern United States will support fresh to strong winds over the
northern and eastern Gulf of Mexico tonight, with easterly gales
offshore Florida through Fri. Low pressure will form in the SW
Gulf Fri night then move NE and into Florida Sat night. This will
cause additional gales in the NE Gulf. A cold front will trail
from the low, exiting the Gulf by early Sun. Expect widespread
showers and thunderstorms over most of the central and eastern
Gulf through early Sun. Strong north winds will spill into the
western Gulf Sat and Sat night behind the front. High pressure
will then settle in over the area through early next week allowing
for marine conditions to improve.

...CARIBBEAN SEA...

Fresh to strong NE winds over most of the central basin, with the
strongest winds noted offshore Colombia, within the Windward
Passage, south of Hispaniola, and in the NW Caribbean north of
20N. Moderate to fresh winds are noted elsewhere. Seas are up to
12 ft offshore Colombia, 8 to 10 across the central basin and 6 to
8 ft elsewhere.

For the forecast, strong high pressure N of the region will
support fresh to strong trade winds across much of the basin into
tonight, before they gradually diminish. A cold front will move
through the Yucatan Channel and into the NW Caribbean Sat night
into Sun. Fresh to strong NW winds may follow this front.

...ATLANTIC OCEAN...

Please read the SPECIAL FEATURES section for details about the
the ongoing Gale Warnings and the Significant North Swell.

A cold front extends from 31N61W, transitioning to stationary
near the northern Bahamas. Aside from those conditions described
above under Special Features, an area of fresh to strong winds is
noted south of 24N and west of 55W to the Greater Antilles, where
seas are 8 to 10 ft. Elsewhere, moderate to fresh winds along
with moderate seas are throughout the rest of the basin.

For the forecast, the front off Florida will become fully
stationary and oriented along 24N by the weekend. The combination
of strong high pressure building north of the area and the front
will result in near gale to gale force northeast to east winds and
building seas over the waters W of 74W and north of 25N into Fri
night, with these winds spreading north- northeastward to the
north- central forecast waters Sun night through Mon night. The
front will then lift N as a warm front while slowly dissipating,
in advance of a low pressure that will cross Florida from the Gulf
of Mexico Sat night. This low will move through the NW Atlantic
waters Sun or Sun night. A large area of gales is likely E of the
low. Widespread showers and thunderstorms are expected over most
of the western half of the area through the weekend.

$$
AReinhart
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