000
AXNT20 KNHC 162341
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST TUE DEC 16 2008

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.

...THE ITCZ...
ITCZ IS CENTERED ALONG 7N12W 4N30W 6N40W 3N51W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION IS FROM 2N-6N BETWEEN 
18W-34W. SCATTERED MODERATE CONVECTION IS FROM 5N-7N BETWEEN 
38W-40W.  

...DISCUSSION...

GULF OF MEXICO...
AS OF 2100 UTC...A STATIONARY FRONT EXTENDS FROM S MISSISSIPPI 
NEAR 30N89W TO THE NW GULF OF MEXICO TO TAMPICO MEXICO NEAR 
21N97W TO INLAND MEXICO NEAR 25N100W TO 29N102W. 15 KT NORTHERLY 
WINDS ARE N OF THE FRONT. OVERCAST MULTILAYERED CLOUDS ARE OVER 
THE NW GULF OF MEXICO N OF THE FRONT WITH TEMPERATURES IN THE 
LOW 40'S. HIGH PRESSURE INDUCED SOUTHWESTERLY RETURN FLOW COVERS 
THE REMAINDER OF THE GULF WITH TEMPERATURES IN THE MID 70'S. 
BROKEN LOW CLOUDS ARE OVER THE N GULF N OF 28N WHILE MOSTLY FAIR 
SKIES ARE S OF 28N. IN THE UPPER LEVELS...A LARGE RIDGE IS OVER 
THE GULF OF MEXICO WITH AXIS ALONG 90W. SIGNIFICANT UPPER LEVEL 
MOISTURE IS N OF 25N WHILE STRONG SUBSIDENCE IS S OF 25N. EXPECT 
THE FRONT TO RETROGRADE BACK TOWARDS THE NW GULF STATES OVER THE 
NEXT 24 HOURS LEAVING THE GULF OF MEXICO WITH WARM SE SURFACE 
FLOW. 

CARIBBEAN SEA...
MODERATE TO FRESH TRADEWINDS ARE OVER THE CARIBBEAN SEA WITH 
HARDILY ANY CONVECTION. SCATTERED SHOWERS ARE OVER THE HIGHER 
ELEVATIONS OF PUERTO RICO...HISPANIOLA....JAMAICA...AND CUBA DUE 
TO NORTHEASTERLY FLOW. SCATTERED SHOWERS ARE ALSO INLAND OVER 
CENTRAL AMERICA FROM PANAMA TO BELIZE. IN THE UPPER LEVELS...A 
RIDGE IS OVER THE W CARIBBEAN W OF 70W WHILE AN UPPER LEVEL 
TROUGH IS OVER THE E CARIBBEAN E OF 70W. STRONG SUBSIDENCE 
COVERS THE ENTIRE CARIBBEAN AND CENTRAL AMERICA. A THIN BAND OF 
UPPER LEVEL CLOUDS EXTENDS HOWEVER FROM TRINIDAD TO THE ABC 
ISLANDS TO NICARAGUA. EXPECT...LITTLE CHANGE OVER THE NEXT 24 
HOURS.  

ATLANTIC OCEAN...
A STATIONARY FRONT IS OVER THE CENTRAL ATLANTIC ALONG 32N52W 
29N58W. SCATTERED MODERATE CONVECTION IS OVER A LARGE AREA FROM 
28N-32N BETWEEN 45W-54W...AND FROM 23N-28N BETWEEN 45W-50W. GALE 
FORCE WINDS ARE N OF THE FRONT. FURTHER S...A 1010 MB LOW IS 
CENTERED NEAR 25N56W. A SURFACE TROUGH EXTENDS S FROM THE LOW TO 
20N58W. A 1030 MB HIGH IS OVER THE E ATLANTIC S OF THE AZORES AT 
36N27W. IN THE UPPER LEVELS... A RIDGE IS OVER THE W ATLANTIC W 
OF 70W. AN UPPER LEVEL TROUGH IS N OF 15N BETWEEN 50W-70W WITH 
AN EMBEDDED UPPER LEVEL LOW NEAR 26N58W. AN UPPER LEVEL RIDGE IS 
OVER THE CENTRAL ATLANTIC BETWEEN 30W-50W. AN UPPER LEVEL TROUGH 
IS OVER THE E ATLANTIC N OF 10N AND E OF 30W.   

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FORMOSA