000
AXNT20 KNHC 310541
TWDAT 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1240 AM EST Tue Dec 31 2019

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 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0000 UTC surface analysis and satellite imagery through 
0520 UTC.

...MONSOON TROUGH/ITCZ... 

The monsoon trough extends from the coast of Liberia near 06N10W 
to 05N13W. The ITCZ continues from 05N13W to 02N20W 02N30W,
crossing the Equator along 38W, to the coast of Brazil near 
02S44W. Precipitation: Isolated moderate to locally strong within
135 nm to the north of the ITCZ from 40W eastward, and to the 
south of the monsoon trough/ITCZ from 30W eastward. Widely
scattered moderate to isolated strong is from 01N southward from
40W westward. 

GULF OF MEXICO...

Large scale SW wind flow, from 250 mb to 500 mb to 700 mb
according to the latest GFS model, spans the Gulf of Mexico.
A cold front passes through north central Florida, into the 
eastern Gulf of Mexico, to the south central Gulf of Mexico,
to a 1012 mb low pressure center that is near 21N95W. The cold 
front continues from the 1012 mb low pressure center, inland,
to the Isthmus of Tehuantepec of southern Mexico. Precipitation: 
broken to overcast low level and middle level clouds, and areas of rain,
are from 22N northward from 90W eastward, from 23N northward 
between 90W and 93W, and from 93W westward.

The current weak cold front will stall from the Straits of 
Florida, to a weak low pressure center that is near Tampico 
Mexico, by Tuesday afternoon. The low pressure center and the 
accompanying front should dissipate on Wednesday. Fresh to strong 
SE to S return flow should set up in most of the Gulf of Mexico on
Wednesday and Thursday. A stronger cold front will move off the 
Texas coast on Thursday night. The stronger cold front will reach 
from the Florida Panhandle to the Bay of Campeche by on Friday 
afternoon. The stronger cold front will push to the south and east
of the Gulf of Mexico by Saturday afternoon.

CARIBBEAN SEA...

The GFS model, for 500 mb and for 700 mb, shows cyclonic wind flow
in the western sections of the Caribbean Sea, from Jamaica
westward, with an inverted trough. Comparatively drier air in
subsidence covers most of the area that is from 80W eastward, and
in the Atlantic Ocean from 10N to 20N between 40W and 60W.

Broad surface low pressure covers the SW corner of the Caribbean
Sea. The monsoon trough reaches the western part of Panama, along
08N/09N near 81W. Precipitation: isolated to widely scattered
moderate and isolated strong from 10N southward from the coast of
Colombia westward. Upper level SW wind flow is pushing the
moisture from the area of the monsoon trough into the SW corner of
the Caribbean Sea.

The Bermuda High, to the north of the area, is supporting fresh 
to strong NE to E trade winds in most of the central Caribbean 
Sea. The wind speeds will diminish some, from late Tuesday through
Saturday night, as the Bermuda High shifts eastward and weakens. 
A strong cold front, on Saturday, should reach the NW Caribbean 
Sea. Long-period N swell is propagating through the Atlantic Ocean
passages and the tropical Atlantic Ocean off the Leeward and 
Windward Islands. This large N swell will diminish by Wednesday. 

ATLANTIC OCEAN...

A cold front passes through 32N77W in the Atlantic Ocean, to north
central Florida. The cold front continues into the eastern Gulf of
Mexico, to the south central Gulf of Mexico, and eventually into
the SW corner of the Gulf of Mexico. Precipitation: broken to
overcast multilayered clouds and possible rainshowers are to the
NW of the line that extends from 25N80W beyond 32N68W. 

An upper level trough is in the eastern sections of the Atlantic
Ocean, along 32N33W 23N37W 15N44W 11N50W. A surface trough is 
along 30N30W 25N33W 17N37W. Precipitation: rainshowers are 
possible within 120 nm on either side of the surface trough.

A ridge from the Bermuda High, that extends across the forecast 
waters, will shift to the east of the area by late Tuesday. A 
weak cold front, moving southeastward off the NE Florida coast, 
will reach from near Bermuda to the central Bahamas on Wednesday 
afternoon. The front will stall and weaken along roughly 25N by 
Thursday afternoon, and then dissipate on Friday. A stronger cold
front should move off the NE Florida coast by late Friday, and 
reach the NW Bahamas by Saturday. 

$$
MT