000
AXNT20 KNHC 152307
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Thu Dec 16 2021

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 
2200 UTC.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of Guinea-Bissau near
11N15W to 06N21W. The ITCZ continues from 06N21W to 04N27W to
05N35W to 03N49W. Scattered moderate and isolated strong
convection is noted from 01N to 08N between 10W and 25W. Isolated
moderate convection is from 02N-09N between 25W-43W.

GULF OF MEXICO...

High pressure ridging dominates the Gulf of Mexico. Moderate winds
prevail across the basin, except for fresh SSE off the coast of
southern Texas and fresh NE to E in the Florida Straits and SE
Gulf of Mexico. Seas of 3 to 5 ft prevail across the basin, except
5-6 ft in the Yucatan Channel and Florida Straits. No significant
areas of precipitation are noted at this time.

For the forecast, high pressure will prevail across the northern
Gulf of Mexico through Sat, supporting moderate to locally fresh 
winds. A cold front is forecast to enter the basin Saturday night 
into early Sunday. Fresh to strong winds and building seas will 
prevail west of the front.

CARIBBEAN SEA...

An east-west oriented surface trough extends from 15N79W to near
the NW coast of Honduras. Scattered moderate to isolated strong
thunderstorms prevail from 14.5N to 17N between 75W and 87W...and
from 16.5N to 18N between 87W and 92W, including over Belize,
northern Guatemala and northeastern Honduras. Scattered showers
and tstorms are also noted over southern Jamaica, enhanced by
afternoon heating. In the SW Caribbean, the east Pacific monsoon
trough is enhancing scattered moderate convection south of 12N and
west of 78W. Fresh easterly trade-winds continue over the majority
of the Caribbean Sea, locally strong in the Windward Passage and
south of Hispaniola. Seas are 6 to 8 ft across the basin.

For the forecast, strong high pressure will prevail over the 
western Atlantic through the forecast period. This will support 
fresh to strong trade-winds over the eastern and central Caribbean
through the weekend. Moderate to fresh trades are expected 
elsewhere. 

ATLANTIC OCEAN...

A fairly strong pressure gradient is over the western Atlantic, in
between 1033 mb high pressure over southern Virgina and a 1008 mb
Colombian low near 10N76W. Fresh to strong E winds prevail south
of 29N to the Greater Antilles, between 70W and the coast of
Florida, including the Bahamas region. A surface trough extends 
from 26N66W to 28.5N68.5W. Isolated showers and tstorms are from 
23.5N to 28N between 63W and 73W, enhanced by an upper-level 
trough located just west of this area. Fresh to strong E winds are
east of the trough, generally from 24N-29N between 59W-70W. A cold
front enters the area near 31N51W to 30N55W to 31N63W. Strong
winds are building seas are N of the front. A surface trough
extends from 31N41W to 24N59W with isolated showers along it.
Fresh N winds are N of the trough, while gentle winds are south of
it and east of 53W. Moderate winds are south of the trough and
west of 53W. A 1012 mb low pressure is near 30N18W, generating
moderate to fresh winds in its western semicircle. Gentle to
moderate winds prevail elsewhere east of 45W. Fresh trades are
noted from 09N-23N, west of 45W, where seas are 7-8 ft. West of 
50W, seas are generally 6-9 ft, except up to 11 ft behind the 
cold front near 31N56W. East of 45W, seas are generally 5-7 ft, 
except to 8 ft near the aforementioned low pressure just N of the 
Canary Islands.

For the forecast, fresh to strong winds will continue west of 65W,
especially south of 27N, through Thu as high pressure north of 
the area builds southward. The cold front extending from 31N51W 
to 30N55W to 31N63W will push southward, reaching from 31N37W to
25N55W to 31N69W by early Thu, and from 31N32W to 22N57W to 31N70W
Thu evening. Strong winds and large N swell will follow the
front, spreading seas of 12-17 ft across the central Atlantic Thu
into Fri. Seas of 8-12 ft will prevail across waters between
65W-75W late this week. Winds and seas will then subside north of
25N and west of 55W over the weekend as high pressure moves
overhead that area. Another cold front may bring increasing winds
and seas north of 27N between 40W and Florida by early Mon.

$$
Hagen