[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 121027
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Thu Jan 12 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 0600 UTC surface analysis and satellite imagery through
1015 UTC.

...SPECIAL FEATURES

Gulf of Mexico Gale Warning: A cold front is forecast to enter
the northwestern and north-central Gulf Thursday morning. It will
reach from Tampa Bay, Florida southwestward to near Veracruz,
Mexico Fri morning. The gradient between the front and strong
high pressure building in behind it will bring near gale to gale
force northerly winds off Veracruz from Fri morning through late
Fri evening. Seas will build and reach 8 to 10 ft by early Fri
morning, then to a higher range of 10-14 ft early Fri afternoon.
Winds and seas will start to diminish late Fri night into early
Sat as the high pressure slides eastward allowing for the
gradient to relax.

Please read the latest NWS Offshore Waters Forecasts issued by
the National Hurricane Center at the website
https://www.nhc.noaa.gov/marine/offshores.php and the High Seas
Forecast at the website
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough axis extends west-southwestward from near the
Sierra Leone/Liberia border into the Atlantic to near 04N21W,
where overnight scatterometer data indicates that it transitions
to the ITCZ to 03N30W and to near 02N40W. Numerous moderate to
isolated strong convection is increasing within 120 nm south of
trough and ITCZ between 14W-25W and between 27W-36W. Similar
convection is within 60 nm north of the ITCZ between 20W-27W and
between 28W-37W.

...GULF OF MEXICO...

Please see the Special Features section for more information on
an upcoming Gale Warning.

A surface ridge extends west-southwestward from a 1022 mb high
over central Florida to near Veracruz, Mexico. Moderate to fresh
south to southwest winds are over the NW Gulf, and moderate to
fresh east to southeast winds are near and along the northern
coast of the Yucatan Peninsula per latest ASCAT data and buoy
observations from the NW Gulf. Seas in the range of 4-6 ft are
over the NW Gulf and over the south-central Gulf near the Yucatan
Peninsula. Gentle to moderate southerly winds, with lower seas
in the range of 2-4 ft are elsewhere over the Gulf.

For the forecast, high pressure over the area will shift eastward
today in response to a cold front that will move off the Texas
coast this morning. Fresh southerly return flow is expected ahead
of the front. Strong northerly winds and building seas will follow
the front, which is forecast to reach from near Tampa Bay,
Florida to Veracruz, Mexico by early Fri. Winds to gale force and
rough seas are possible off Veracruz behind the front on Fri, with
fresh to strong northerly winds elsewhere. Winds and seas will
diminish from W to E into Sat as the front moves southeast of the
area. Afterward, fresh to strong southerly return flow is expected
to develop across the western Gulf on Sun along with building
seas. The fresh to strong return will expand eastward through Mon,
then diminish to moderate Mon night.

...CARIBBEAN SEA...

A surface ridge associated to a 1022 mb high center located over
central Florida continues to control the trade wind regime across
the entire basin. Moderate to fresh trade winds are over the
south-central basin, with fresh to strong northeast to east winds
near and offshore the coast of Colombia. Seas in this part of the
basin are in the 5-7 ft range, except for slighter higher seas of
6-8 ft seas near the coast of Colombia. Gentle to moderate
northeast to east trade winds, with seas of 3-5 ft are over the
remainder of the sea. Isolated light showers moving quickly
westward are possible in the eastern Caribbean and in the far
southwestern part of the sea near the coasts of Costa Rica.

For the forecast, pulsing fresh to strong northeast to east trade
winds in the south-central Caribbean and near the coast of
Colombia will continue through Fri night, then return Sun night
through early next week. Moderate to fresh trade winds over most
of the basin will continue through this morning. A cold front will
reach the Yucatan Channel by Fri night followed by fresh to
locally strong NW to N winds. The front will reach from eastern
Cuba to the Gulf of Honduras on Sat afternoon, and from Haiti to
near Cabo Gracias a Dios, Nicaragua Sat night into Sun. The front
could reach the northeastern Caribbean Sun night through Mon night
as it weakens to a shear line.

...ATLANTIC OCEAN...

A stationary front extends southwestward from the north-central
Atlantic across 31N51W and to near 23N63W. Fresh southwest winds
are ahead of the front reaching eastward to near 48W. Seas with
these winds are 5-7 ft. Numerous showers and isolated thunderstorms
are noted within 60 nm east of the front north of 27N. This
activity is being aided by rather vigorous jet stream dynamics
ahead of a very pronounced upper-level trough that is behind the
frontal boundary. An area of scattered showers and isolated
weakening thunderstorms is seen over the waters east of
northeastern Brazil from about 01N to 10N between 43W and the
coast of northeastern Brazil. Low-level speed convergence of
northeast trade winds is helping to sustain this activity.
Refer to the Monsoon Trough/ITCZ section for additional
convection in the Atlantic Basin.

Elsewhere, Atlantic high pressure is supporting mostly gentle
winds, with seas of 5-8 ft seas north of 26N between 35W and 60W.
Seas of 3-6 ft are present west of 60W, with the exception of
lower seas of 2-3 ft west of 75W. Seas of 1 ft or less are over
the within the Bahamas. Gentle to moderate northeast to east
winds are over this part of the area, with the exception of
gentle to moderate southwest winds offshore northeast Florida.
In the far southeast part of the area, mostly fresh northeast to
east trade winds are noted. Seas of 7-10 ft due to a long-period
northeast swell are present north of 05N between the African coast
and 35W, and also from 04N to 26N between 35W and 53W. Gentle
with locally moderate southerly and monsoonal winds with seas at 4
to 6 ft in southerly swell prevail elsewhere.

For the forecast west of 55W, the aforementioned stationary front
will begin to shift eastward as a cold front once again starting
this morning, moving east of 55W by early this evening, with
high pressure building in behind it. A strong cold front will
move off the northeast Florida coast early Fri. As the front moves
eastward across the western Atlantic, expect increasing winds and
building seas. Fresh to strong winds are forecast on either side
of the front during the upcoming weekend. These winds could reach
gale force across the waters N of 29N late Sat into early on Sun.
Seas of 12-15 ft are anticipated with the strongest winds NE of
the Bahamas.

$$

Forecaster Aguirre
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