[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 210515
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0605 UTC Wed Dec 21 2022

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 0000 UTC surface analysis and satellite imagery through
0455 UTC.

...SPECIAL FEATURES...

Gulf of Mexico Gale Warning: A 1016 mb low pressure is centered
near 28.5N88W with a cold front extending south-southwestward
from the low to 18.5N94W and a warm front extending eastward from
the low to Cedar Key, Florida. A recent scatterometer satellite
pass show strong to near gale-force winds over the northern and NW
Gulf. Buoy 42036 near 28.5N 84.5W recorded a sustained 1-min wind
of 33 kt gusting to 43 kt at 21/0310 UTC at an elevation of 4
meters. Seas are 6-9 ft across the northern and NE Gulf. Winds in
the NE Gulf should diminish below gale force in the overnight
hours. Meanwhile, gale force NW winds are likely occurring within
60 nm of the coast of Vercruz, Mexico behind the cold front.
Winds are forecast to diminish below gale force there around
21/0600 UTC. Seas are currently peaking at around 12 ft. The low
will continue moving ESE across the Gulf of Mexico Wed, with a
cold front extending SSW and a warm front extending E from the
low. Winds and seas will quickly diminish Wed afternoon and
evening.

West Atlantic Gale Warning: A low pressure over the Gulf of
Mexico will cross South Florida tonight and move east-northeast
near the NW Bahamas by Wed morning. The low will support NE to E
gale force winds Wed through Wed evening just northeast of the
Bahamas, as the low moves eastward along 26/27N. These gales
should diminish by early Thursday as the low reaches near 26N65W.
At the same time, a second area of gales is affecting the waters
east of N Florida, associated with a separate low pressure along
a sharp surface trough. A recent scatterometer satellite pass
indicate that strong to gale-force winds are occurring north of
28N and west of 77W. A buoy just north of the area has been
gusting to 35 kt during the past couple of hours. Seas in these
waters are 8-12 ft. Winds will gradually weaken in our waters
south of 31N Wed night as the trough lifts northeastward. Peak
seas should reach around 10-11 ft northeast of the Bahamas and
12-13 ft east of N Florida Wed.

Please read the latest High Seas Forecast issued by the National
Hurricane Center at http://www.nhc.noaa.gov/text/MIAHSFAT2.shtml
for more details on both Gale Warnings.

...MONSOON TROUGH/ITCZ...

The monsoon trough enters the Atlantic through the coast of
Guinea near 11N15W and continues to 05N22W. The ITCZ then extends
from 05N22W to 02N37W to 03N51W. A few showers are noted south of
the monsoon trough and east of 20W. Similar convection is observed
south of the ITCZ and between 24W and 38W.

GULF OF MEXICO...

Please read the Special Features section above for information
on the two gale areas over the Gulf of Mexico. Scattered moderate
to isolated strong convection is noted in the NE Gulf, north of
27N and east of 85W.

Outside of the impacts of the low pressure and frontal boundaries
mentioned above in the Special Features section, gentle to
moderate winds are occurring south of 26N and east of 91.5W,
where seas are 3-5 ft. Seas in the strong winds west of the cold
front and north of the stationary front are mostly 6 to 8 ft.

For the forecast, looking ahead, a stronger cold front is
expected to move off the Texas coast Thu evening followed by near-
gale to gale force NW winds and rough to very rough seas across
the basin through Fri night, with strong gales possible off
Veracruz beginning of Fri. Conditions will slowly improve through
the upcoming weekend.

CARIBBEAN SEA...

High pressure over the eastern United States extends southward
into the Caribbean Sea, maintaining fairly tranquil weather
conditions, except for a few pockets of shallow moisture moving
through the NW Caribbean. The pressure gradient between the ridge
to the north and lower pressures in northern South America sustain
mainly fresh to strong easterly trade winds in the central
Caribbean, with the strongest winds occurring off NW Colombia and
in the Gulf of Venezuela. A recent scatterometer satellite pass
captured near gale-force winds off NW Colombia. The seas in these
waters are 5-8 ft. Moderate to locally fresh easterly breezes and
seas of 3-6 ft are present in the eastern Caribbean. Elsewhere,
light to locally moderate easterly winds and slight seas prevail.

For the forecast, surface ridging north of the region will support
pulsing fresh to strong NE to E tradewinds across the central
and SW Caribbean through the week and weekend. Moderate to fresh
winds will prevail in the E Caribbean with gentle to moderate
winds in the W Caribbean. Moderate long-period N to NE swell
will continue to move into the tropical Atlantic waters for the
next several days. A cold front will move into the Yucatan
Channel by late Fri and reach from central Cuba to Belize by Sat
night, dissipating from eastern Cuba to eastern Honduras Sun.
Fresh to locally strong winds and rough seas will follow the
front.

ATLANTIC OCEAN...

Please read the Special Features section for details on two gale
warnings in the western Atlantic.

A cold front extends from 31N47W to 25N58W, where it becomes a
stationary front that continues southwestward to 23N67W, becoming
a shear line that extends westward to the Florida Straits.
Isolated to scattered moderate convection is present near the cold
front. Fresh to strong easterly winds are noted behind the frontal
boundaries, especially south of 28N and west of 67W. Moderate to
locally fresh northerly winds are found in the remainder of the
western atlantic behind the frontal boundaries. Seas are 5-11 ft
behind the frontal boundaries, with the highest seas occurring
north of 30N and east of 67W. Moderate to fresh SW winds and seas
of 6-10 ft are noted ahead of the cold front, north of 27N and
west of 40W. Moderate to fresh trade winds are found between the
SE Bahamas and eastern Cuba and northern Hispaniola, including the
entrance to the Windward Passage. Seas in these waters are 3-5 ft.

The rest of the tropical Atlantic is dominated by a broad ridge
positioned over the NW Africa. The pressure gradient between this
high pressure and lower pressures in the deep tropics support
moderate to fresh trade winds south of a line from the Canary
Islands to the Leeward Islands. The northerly swell is producing
seas of 6-9 ft in these waters, with the highest seas occurring
near 06N45W. Moderate or weaker winds and moderate seas prevail
elsewhere in the basin.

For the forecast west of 55W, the aforementioned front will
continue moving slowly E tonight. A low pres currently over the
Gulf of Mexico will cross South Florida tonight and move ENE near
the NW Bahamas by Wed morning. NE gale-force winds will accompany
that low Wed and Wed night. Another low will develop N of the area
along 80W with gale-force winds tonight and Wed morning. Winds
will become southerly Thu ahead of a stronger cold front expected
to move off the northeast Florida coast Fri, accompanied by strong
to near- gale force NW winds and rough seas. NW gales are
possible to the east of northern Florida with this front.

$$
DELGADO
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