000
AXNT20 KNHC 091731
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST TUE DEC 09 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1700 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 4N9W 3N18W 1N29W TO THE EQUATOR AT 
45W. CLUSTERS OF ISOLATED MODERATE CONVECTION ARE FROM 7N TO THE 
EQUATOR BETWEEN 22W TO 42W.

...DISCUSSION...

GULF OF MEXICO...
A COLD FRONT IS ANALYZED OVER THE NW GULF OF MEXICO ALONG 29N91W 
27N94W 27N97W. THIS SYSTEM IS MOVING TO THE EAST BRINGING ALONG A 
LINE OF HEAVY SHOWERS AND THUNDERSTORMS AHEAD OF IT MOVING ACROSS 
THE FLORIDA PANHANDLE. THIS LINE OF SHOWERS IS ENHANCED BY A SURFACE 
TROUGH THAT IS 100 NM AHEAD OF THE COLD FRONT. SOUTHERLY FLOW 10-20 
KTS AHEAD OF THE FRONT IS PROVIDING SUFFICIENT MOISTURE TO THIS 
SYSTEM. A 1005 MB SURFACE LOW IS FOUND OVER THE WESTERN GULF. 
NEVERTHELESS...VERY LITTLE ACTIVITY IS FOUND IN THIS REGION. 
DIFFLUENT FLOW ALOFT IS NOTED ACROSS THE BASIN. EXPECT THE FRONT TO 
MOVE FURTHER EASTWARD INTO NORTHERN FLORIDA WITH CONTINUING SHOWERS 
AND THUNDERSTORMS AFFECTING THE EASTERN GULF. 

CARIBBEAN SEA...
A BROAD UPPER RIDGE EXTENDS ACROSS THE CARIBBEAN INTO THE ATLC 
GIVING THE ENTIRE BASIN STRONG SUBSIDENCE. NEVERTHELESS...SCATTERED 
SHOWERS ARE OVER THE N/CENTRAL CARIBBEAN N OF 15N TO OVER HISPANIOLA 
BETWEEN 70W-76W. ISOLATED SHOWERS CAN BE FOUND ACROSS THE REMAINDER 
OF THE N CARIBBEAN BETWEEN 15N-20N. SURFACE RIDGE N OF THE CARIBBEAN 
IS MAINTAINING MODERATE TO FRESH EASTERLY TRADE WINDS ACROSS THE 
REGION AND IS EXPECTED TO INCREASE OVER THE E CARIBBEAN BEGINNING 
THURSDAY.

ATLANTIC OCEAN...
SURFACE HIGH PRESSURE OVER THE NORTH-CENTRAL ATLANTIC IS DOMINATING 
THE WEATHER PATTERN IN THIS REGION. THIS SURFACE HIGH IS WELL 
CORRELATED TO A BIG UPPER LEVEL RIDGE OVER THE WESTERN ATLANTIC. 
THIS FEATURE WILL MAKE THE SURFACE HIGH TO SLOWLY PROGRESS 
EASTWARD...MAINTAINING FAIR WEATHER ACROSS THE CENTRAL PORTION OF 
THE ATLANTIC DURING THE NEXT 24 HOURS. A SURFACE TROUGH IS 
DISTINGUISHED ALONG 30N41W 28N45W 26N51W 26N59W. THIS TROUGH IS 
SUPPORTED BY AN UPPER LEVEL TROUGH OVER THE EAST-CENTRAL ATLANTIC. 
HOWEVER...VERY LITTLE ACTIVITY IS ASSOCIATED WITH THIS TROUGH. MOST 
OF THE ACTIVITY IS SEEN 300 NM NORTHEAST OF 30N41W. AN AREA OF 
MODERATE CONVECTION IS OVER THE SOUTHEASTERN ATLANTIC FROM 12N TO 7N 
BETWEEN 17W AND 26W. THIS AREA OF MODERATE CONVECTION IS EXPECTED TO 
DIMINISH OVER THE NEXT 24 HOUR. 

$$

GARCIA