[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 131744
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Fri Jan 13 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 1200 UTC surface analysis and satellite imagery through
1725 UTC.

...SPECIAL FEATURES...

SW GULF OF MEXICO GALE WARNING:

As of 1500 UTC, a strong cold front extends from the SW Florida
to the eastern Bay of Campeche. The tight pressure gradient due to
a 1033 mb high pressure system over northern Mexico supports
gale-force northerly winds off Veracruz, while fresh to strong
winds prevail elsewhere behind the front. A recent scatterometer
satellite pass also showed gale-force winds occurring in the SW
Bay of Campeche. Seas are peaking near 12 ft off Veracruz. Gales
will persist through tonight. Conditions are expected to improve
west to east on Sat across the Gulf.

WESTERN ATLANTIC GALE WARNING:

As of 1500 UTC, a strong cold front is exiting off NE Florida and
forecast to move eastward across the western Atlantic during the
weekend. A recent scatterometer satellite pass show fresh to
strong SW winds ahead of the frontal boundary. Winds will increase
to gale-force off NE Florida tonight and north of 28N and between
68W and 65W by Sat morning. Gales will moves eastward on Sat and
Sun, remaining north of 28N and reaching to 55W by late Sun. Seas
are forecast to build behind the front to near 15 ft by late Sat
and ahead of the front to near 16 ft by Sun. Conditions will
gradually improve on Mon and Tue, with seas dropping below 12 ft
by the middle of next week.

Please, read the latest NWS High Seas Forecast issued by the
National Hurricane Center at website:
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, for more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic Ocean through the coast of
Liberia near 06N10W to 04N25W. The ITCZ extends from 04N25W to 03N37W
to 01N50W. Scattered moderate convection is observed south of 06N
and east of 30W.

GULF OF MEXICO...

Please read the SPECIAL FEATURES above for more on a Gale Warning
over the SW Gulf of Mexico.

As of 1500 UTC, the strong cold front moving across the Gulf of
Mexico stretches from SW Florida to the NW Yucatan peninsula to
Veracruz, Mexico. A line of fast-moving showers and isolated
thunderstorms is affecting the SE Gulf waters, especially from SW
Florida to near NW Cuba and then to NE Yucatan. Behind the front,
the dry and cold arctic airmass moving over the warmer Gulf
waters result in stratocumulus clouds covering most of the basin.
A recent scatterometer satellite pass indicate that fresh to
strong northerly winds are present behind the cold front, except
for the gale-force winds occurring off Veracruz and covered in the
Special Features section. Seas are 6-11 ft in these waters. Ahead
of the front, moderate W-SW winds and slight to moderate seas
prevail.

For the forecast, aside from the gales, high pressure will move
across the basin this weekend, with strong southerly return flow
developing in the NW Gulf early Sun. Winds will diminish Mon
night.

CARIBBEAN SEA...

Isolated patches of low-level moisture moving across the
Caribbean Sea are generating some shower activity, especially in
the Windward Passage region. A generally dry airmass dominates
most of the basin, suppressing the development of deep convection.
Clear skies and calm winds allowed for temperatures to drop below
10 degrees Celsius in areas of central and western Cuba last
night. The cold front in the Gulf of Mexico is quickly approaching
the NW Caribbean and scattered moderate to isolated strong
convection is likely to develop in the area this afternoon and
tonight.

A recent scatterometer satellite pass show moderate to fresh
easterly trade winds in the central and eastern Caribbean Sea.
Seas in these waters are 4-7 ft, with the highest seas occurring
offshore NW Colombia. Light to gentle northerly winds and slight
seas are prevalent in the remainder of the basin.

For the forecast, fresh to strong northeast to east trade winds will
pulse in the south-central Caribbean and near the coast of
Colombia Sun night into late next week. A cold front will reach
the Yucatan Channel today followed by fresh to locally strong NW
to N winds. By early Sun this front will reach from the Windward
Passage to the Nicaragua Honduras border, then weaken to a shear
line over the NE Caribbean on Mon.

ATLANTIC OCEAN...

Please read the SPECIAL FEATURES above for more on a Gale Warning
associated with the cold front entering the western Atlantic.

The cold front moving across the Gulf of Mexico has now pushed
into the offshore waters of NE Florida. Scattered moderate
convection is noted ahead of the frontal boundary, mainly west of
75W. Recent scatterometer wind data indicate that the convection
is generating wind gusts to gale force. The strongest convection
is occurring off the SE US coast, north of our region. Overall,
fresh to strong southerly winds are evident ahead of the frontal
boundary, mainly north of 26N and west of 67W. Fresh to locally
strong winds are noted behind the frontal boundary. Seas are 5-10
ft north of 26N and west of 67W. Farther southeast, a weak surface
trough is draped across the SE Bahamas, especially along 72W,
extending from 21N-25W. Scattered moderate convection is seen
within 150 nm on both sides of the trough axis. Satellite-derived
wind data show that fresh to locally strong E-SE winds are
occurring with the strongest convection. The rest of the western
tropical Atlantic, W of 55W, is dominated by a 1023 mb high
pressure system located SE of Bermuda, supporting moderate or
weaker E-SE winds and moderate seas.

Another cold front extends from 31N45W to 26N51W, where it becomes
a dissipating cold front to 21N62W. Scattered moderate convection
is noted ahead of the frontal boundary north of 27N and west of
43W. A weak surface trough is located east of the Lesser Antilles,
along 57W and extending from 13N-18N. Scattered showers are seen
about 100 nm on other side of the trough axis. The remainder of
the central and eastern tropical Atlantic is dominated by a 1033
mb high pressure system between the Azores and the Madeira
Islands. The pressure gradient between the ridge and lower
pressures over western Africa and the deep tropics sustain a large
area of fresh to locally strong NE-E winds, mainly north of 20N
and east of 33W. Seas in these waters are 6-10 ft. Moderate or
weaker winds and moderate seas prevail elsewhere.

For the forecast W of 55W, the cold front exiting NE Florida will
track east across the area through the weekend. Strong southerly
winds ahead of the front will increase to gales N of 28N this
weekend. Strong winds are also expected behind the front, with
seas building to 12 to 15 ft. A period of NW gales is likely Sat
behind the front offshore NE Florida.

$$
DELGADO
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