000
AXNT20 KNHC 271737
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST TUE DEC 27 2011

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE N COAST OF LIBERIA AT 7N11W 
TO 5N18W. THE ITCZ AXIS CONTINUES TO N BRAZIL ALONG 5N18W 4N30W 
2N50W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 3N-6N 
BETWEEN 10W-14W...AND FROM 4N-7N BETWEEN 20W-25W. SCATTERED 
MODERATE CONVECTION IS FROM 1N-5N BETWEEN 26W-35W...AND FROM 
3N-5N BETWEEN 38W-40W. 

...DISCUSSION...

GULF OF MEXICO...
A COLD FRONT IS OVER THE GULF OF MEXICO FROM THE FLORIDA 
PANHANDLE AT 30N84W TO THE GULF OF CAMPECHE ALONG 27N85W 20N93W. 
BROKEN TO OVERCAST LOW CLOUDS ARE WITHIN 120 NM NW OF THE FRONT 
WITH SCATTERED SHOWERS WITHIN 30 NM. MOSTLY CLEAR SKIES ARE OVER 
THE REMAINDER OF THE NW GULF. A PREFRONTAL BAND OF SHOWERS ARE 
NOTED OFF THE COAST OF SW FLORIDA FROM 24N-26N BETWEEN 82W-84W.  
15-20 KT NW SURFACE WINDS ARE N OF THE FRONT WHILE 15-20 KT S 
WINDS ARE S OF THE FRONT. A GOOD AMOUNT OF COLD AIR ADVECTION IS 
BEHIND THE FRONT ESPECIALLY OVER N FLORIDA. IN THE UPPER 
LEVELS...AN UPPER LEVEL TROUGH IS OVER THE CENTRAL GULF 
SUPPORTING THE SURFACE FRONT. STRONG SUBSIDENCE COVERS THE 
ENTIRE GULF. EXPECT...THE FRONT TO EXTEND FROM THE STRAITS OF 
FLORIDA TO THE YUCATAN PENINSULA IN 24 HOURS WITH SCATTERED 
SHOWERS. EXPECT TEMPERATURES TO BE LOWER YET OVER FLORIDA IN 48 
HOURS.    

CARIBBEAN SEA...
20-25 KT TRADEWINDS ARE OVER THE CENTRAL CARIBBEAN BETWEEN 
70W-80W WITH STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. IN 
CONTRAST 10-20 KT TRADEWINDS ARE OVER THE W CARIBBEAN WITH 
LIGHTEST WINDS OVER THE YUCATAN CHANNEL. 15-20 KT TRADEWINDS ARE 
OVER THE E CARIBBEAN. PATCHES OF BROKEN LOW CLOUDS WITH 
SCATTERED SHOWERS DOTS THE CARIBBEAN MOVING W WITH THE 
TRADEWINDS ESPECIALLY OVER TRINIDAD...AND E HISPANIOLA. SIMILAR 
SHOWERS ARE INLAND OVER NICARAGUA...HONDURAS...AND GUATEMALA. IN 
THE UPPER LEVELS...ZONAL FLOW WITH STRONG SUBSIDENCE COVERS THE 
CARIBBEAN AND CENTRAL AMERICA SUPPRESSING ALL DEEP CONVECTION.
EXPECT IN 24 HOURS FOR...THE COLD FRONT OVER THE GULF OF MEXICO 
TO PRODUCE ADDITIONAL SHOWERS OVER THE YUCATAN PENINSULA AND 
YUCATAN CHANNEL. EXPECT LITTLE CHANGE OVER THE REMAINDER OF THE 
CARIBBEAN.  

ATLANTIC OCEAN...
PREFRONTAL LOW CLOUDINESS AND SCATTERED SHOWERS ARE ALONG THE 
COAST OF N FLORIDA N OF COCOA BEACH MOVING E. A 1025 MB HIGH IS 
OVER THE W ATLANTIC NEAR 34N69W. A COLD FRONT IS OVER THE 
CENTRAL ATLANTIC FROM 30N51W TO 25N60W 25N70W. BROKEN TO 
OVERCAST LOW CLOUDS ARE WITHIN 120 NM NW OF THE FRONT WITH 
SCATTERED SHOWERS WITHIN 30 NM. GALE FORCE WINDS ARE N OF 29N W 
OF FRONT TO 60W AND ARE FORECAST TO REMAIN FOR THE NEXT 18 
HOURS. A SURFACE TROUGH IS OVER THE TROPICS FROM 18N48W TO 
13N51W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE TROUGH. AN 
UPPER LEVEL LOW IS CENTERED W OF THE CAPE VERDE ISLANDS NEAR 
20N30W PRODUCING SCATTERED RAIN AND SHOWERS NEAR THE LOW CENTER 
AND FURTHER E DUE TO UPPER LEVEL DIFFLUENCE. EXPECT IN 24 HOURS 
FOR...A COLD FRONT TO EXTEND OVER THE W ATLANTIC FROM 30N72W TO 
THE STRAITS OF FLORIDA WITH CONVECTION. ALSO EXPECT THE CENTRAL 
ATLANTIC  FRONT TO EXTEND FROM 30N41W TO 20N50W WITH RAIN AND 
SHOWERS.     

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

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FORMOSA