[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 121757
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Tue Dec 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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

...SPECIAL FEATURE...

Central Atlantic Gale Warning:
A low pressure system is forecast to develop in the central
subtropical Atlantic along a stationary front near 25N42W late
tonight. Afterward, it is expected to deepen while drifting
generally northwestward through Thursday. Near-gale to gale
northerly winds will develop just northwest and north of the low
from 26N to 29N between 39W and 42W on Wednesday morning, then
shift westward through Thursday morning. Seas under the strongest
winds are anticipated to peak from 16 to 19 ft. Please read the
latest High Seas Forecast issued by the National Hurricane Center,
at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more
details.

Western and Central Atlantic Significant Swell Event:
Large northerly swell are coupling with wind waves created by
fresh to strong NE winds to create seas of 12 to 15 ft at the
central Atlantic from 22N to 29N between 35W and 58W. This area
will gradually shift southwestward toward Puerto Rico and the
Virgin and northern Leeward Islands through Wednesday night,
before subsiding below 12 ft on Thursday. Please, read the latest
High Seas and Offshore Waters Forecasts issued by the National
Hurricane Center, at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml
and https://www.nhc.noaa.gov/marine/offshores.php for more
details.

...MONSOON TROUGH/ITCZ...

A monsoon trough enters the Atlantic along the Guinea coast near
Conakry, then runs southwestward to near 07N16W. An ITCZ
continues westward from 07N16W across 04N40W to 04N42W. Scattered
moderate convection is seen south of the trough from 01N to 06N
between the Liberia coast and 16W. Widely scattered moderate
convection is present up to 110 nm along either side of the ITCZ.

...GULF OF MEXICO...

A surface trough is seen near the east coast of Mexico from
Veracruz northward to near Galveston, Texas. Widely scattered
moderate convection is found near this feature at the west-
central Gulf. A broad surface ridge reaches southwestward from
the Florida Panhandle to the central Bay of Campeche. Moderate to
fresh with locally strong ENE winds and seas at 5 to 8 ft exist
across the central and eastern Gulf, including the Yucatan Channel
and Florida Straits. Gentle to moderate ENE to ESE winds and 3 to
5 ft seas prevail for the western Gulf.

For the forecast, fresh to locally strong NE winds and rough seas
will prevail over the southeastern Gulf today. Strong high
pressure will build across the eastern United States, increasing
areal coverage of fresh to strong winds over much of the Gulf by
Thursday. A large area of near gale-force winds will develop over
the north-central and northeastern Gulf Thu through Fri night. An
area of low pressure will develop over the southern Gulf toward
the end of the week, and track northeastward across southern
Florida Sat night. The pressure gradient will further tigthen with
gale-force winds possible over the southeastern Gulf Fri. A cold
front will move into the western Gulf this weekend, with strong to
near gale-force winds and rough seas west of the front.

...CARIBBEAN SEA...

A stationary front reaches southwestward from central Cuba across
the Cayman Islands to just east of the Gulf of Honduras. A
surface trough runs northwestward from northeastern Honduras
across the Gulf of Honduras to the Yucatan Peninsula. Scattered
showers and isolated thunderstorms are occurring near and
northwest of these features over the northwestern basin.
Convergent trades are causing widely scattered showers and
isolated thunderstorms along the Nicaragua coast and nearby
waters.

Fresh to strong ENE to E winds and seas of 8 to 12 ft are found at
the central basin. Moderate to fresh with locally ENE winds and 5
to 8 ft seas exist at the eastern and southwestern basin.
Moderate to fresh NE winds and seas at 6 to 9 ft are present over
the northwestern basin, behind the stationary front.

For the forecast, strong high pressure north of the region will
support fresh to strong trade winds across the central and eastern
Caribbean through Wed night. Rough seas in these regions will be
in the 8 to 12 ft range, highest over Colombia adjacent waters. ENE
winds behind the front will become fresh to strong by later this
afternoon and then persist through Wed morning in which the front
will lift northward towards the Straits of Florida and the
southeastern Gulf of Mexico.

...ATLANTIC OCEAN...

Please read the Special Features section at the beginning about a
Gale Warning and significant north swell.

A stationary front stretches southwestward from near Bermuda
across 31N68W across the central Bahamas to beyond central Cuba.
Widely scattered showers and isolated thunderstorms dominate up to
60 nm northwest, and 180 nm southeast of this feature. A cold
front reaches southwestward from west of Madeira to near 31N25W,
then continues as a stationary front to east of the northern
Leeward Islands. Scattered moderate convection is noted up to 170
nm northwest, and 100 nm southeast of this boundary. To the south,
a few surface troughs are triggering widely scattered moderate
convection from 10N to 18N between 43W and 60W.

Fresh to strong NE to ENE winds and seas of 6 to 9 ft are evident
behind the first stationary front, including the northwest Bahamas
and near the Florida east coast. Behind the second stationary
front but outside the significant swell area mentioned in the
Special Features section, moderate to fresh NE to ENE winds and 8
to 11 ft seas are present up to 500 nm northwest of the second
stationary front. For the eastern Atlantic, gentle with locally
moderate NNE to E winds and seas at 4 to 8 ft in moderate NW swell
are seen north of 14N between the Africa coast and 40W/second
stationary front, including the Canary and Cabo Verde Islands.
Farther west, gentle to moderate ENE to ESE winds and 8 to 11 ft
seas in large northerly swell are noted from 06N to 20N/second
stationary front between 40W and the Lesser Antilles. Gentle to
moderate southerly and light to gentle monsoonal winds with seas
of 4 to 7 ft in moderate mixed swells prevail for the remainder of
the Atlantic Basin.

For the forecast W of 55W, the second stationary front is
forecast to lift northward towards the northwest Bahamas and the
Straits of Florida this evening. Strong high pressure building
north of the area will lead to the development of strong to near-
gale force NE to E winds and building seas over the northern
Bahamas and Straits of Florida through Wed, with these winds
spreading northward through Thu night. Gale force winds are
possible east of Florida later this week.

$$

Chan
This weather bulletin was brought to you by:
www.nashvilleweather.net