000
AXNT20 KNHC 022358
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST WED DEC 02 2009

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...METEOROLOGICAL ANALYSIS...WEATHER 
OBSERVATIONS...AND RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2315 UTC.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 10N12W 5N24W 4N51W. ITCZ IS VOID OF 
ANY DEEP CONVECTION WITH ISOLATED SHOWERS WITHIN 120 NM OF THE AXIS 
BETWEEN 16W-41W. 

...DISCUSSION...

GULF OF MEXICO...
AS OF 2100 UTC...A COLD FRONT EXTENDS ACROSS THE GULF ENTERING OVER 
THE FLORIDA PANHANDLE BETWEEN PENSACOLA AND PANAMA CITY ALONG 26N87W 
21N92W INTO S MEXICO JUST E OF VERACRUZ WITH SCATTERED SHOWERS/ 
ISOLATED THUNDERSTORMS WITHIN 150 NM E OF THE FRONT N OF 23N AND 
ISOLATED SHOWERS OVER THE REMAINDER OF FLORIDA E OF THE FRONT. THIS 
FRONT IS BEING SUPPORTED BY AN UPPER LOW MOVING N ALONG THE 
MISSISSIPPI VALLEY/W TENNESSEE. A BROAD UPPER RIDGE OVER THE W 
CARIBBEAN AND W ATLC DOMINATES THE GULF WATERS. A JETSTREAM WITH 
WINDS OF 90 TO 125 KT COVERS THE NW GULF FROM TUXPAN MEXICO TO TAMPA 
FLORIDA AS INDICATED SATELLITE DERIVED WINDS. THE COLD FRONT WILL 
MOVE INTO THE W ATLC TONIGHT/THU MORNING STALLING FROM SW FLORIDA TO 
THE BAY OF CAMPECHE LATER ON THU THEN WILL MOVE BACK N OVER THE GULF 
WATERS THU NIGHT INTO FRI.

CARIBBEAN SEA...
A BROAD UPPER RIDGE COVERS THE CARIBBEAN ANCHORED IN THE E PACIFIC 
EXTENDING ACROSS CENTRAL AMERICA OVER HISPANIOLA AND INTO THE W 
ATLC. STRONG SUBSIDENCE AND THE LACK OF MOISTURE IS NOTED ON WATER 
VAPOR IMAGERY WHICH ACCOMPANIES THE UPPER LEVEL ANTICYCLONIC 
CIRCULATION BRINGING TRANQUIL WEATHER AND FAIR SKIES TO MUCH OF THE 
BASIN. HOWEVER...A FEW ISOLATED SHOWERS ARE BEING USHERED IN ON 
FRESH TO STRONG TRADEWINDS ACROSS THE E CARIBBEAN AND LESSER 
ANTILLES MAINLY E OF 70W. ALSO...A FEW ISOLATED SHOWERS ARE ALONG 
THE COASTS FROM CENTRAL PANAMA TO S NICARAGUA SW OF A LINE FROM 
12N84W TO 9N80W. 

ATLANTIC OCEAN...
THE UPPER RIDGE THAT COVERS THE CARIBBEAN AND GULF OF MEXICO EXTENDS 
OVER THE W ATLC W OF 60W WITH A SURFACE RIDGE COVERING THE W ATLC 
ANCHORED BY A 1027 MB HIGH N OF BERMUDA. HOWEVER...ISOLATED SHOWERS 
ARE OVER THE FAR NW PORTION OF THE DISCUSSION AREA N OF 27N W OF 78W 
ASSOCIATED WITH THE FRONT CURRENTLY OVER THE GULF OF MEXICO. A 
NARROW UPPER TROUGH AXIS EXTENDS ALONG 48W AND IS SUPPORTING A COLD 
FRONT THAT IS N OF THE DISCUSSION AREA AND A SURFACE TROUGH TO THE E 
EXTENDING THROUGH 32N45W TO 19N52W WITH SCATTERED SHOWERS AND 
POSSIBLE ISOLATED THUNDERSTORMS FROM 41W-47W N OF 21N. AN EQUALLY 
NARROW UPPER RIDGE IS JUST TO THE E OF THE UPPER TROUGH ALONG 42W 
PROVIDING DIFFLUENCE ALOFT TO ENHANCE THE ACTIVITY ABOVE. THE E ATLC 
IS DOMINATED BY A SECOND SURFACE RIDGE ANCHORED BY A 1029 MB HIGH 
OVER THE AZORES. THIS SCENARIO IS GIVING THE REMAINDER OF THE W ATLC 
AND E ATLC FAIR WEATHER THIS EVENING. 

$$
WALLACE