000
AXNT20 KNHC 220536
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST THU DEC 22 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE COAST OF SIERRA LEONE NEAR 
9N13W TO 8N16W. THE ITCZ CONTINUES FROM 8N16W TO 5N35W TO 5N52W. 
ISOLATED MODERATE CONVECTION IS FROM 3N-6N BETWEEN 7W-15W... AND 
FROM 3N-8N BETWEEN 27N-32W. 

...DISCUSSION...

GULF OF MEXICO...
A 1009 MB LOW IS OFF THE COAST OF BROWNSVILLE TEXAS AT 26N97W. A 
WARM FRONT EXTENDS NE FROM THE LOW TO LOUISIANA AT 29N90W. RADAR 
IMAGERY SHOWS SCATTERED MODERATE CONVECTION INLAND OVER S TEXAS. 
FURTHER E...SCATTERED SHOWERS ARE NOTED S OF THE FLORIDA 
PANHANDLE N OF 28N BETWEEN 85W-89W. ELSEWHERE...S OF THE WARM 
FRONT 10-20 KT SOUTHERLY RETURN FLOW IS OVER THE GULF OF MEXICO 
WITH FAIR WEATHER AND TEMPERATURES IN THE 70'S. EXPECT THE FRONT 
TO CONTINUE TO MOVE TOWARDS THE TEXAS COAST UNTIL 1200 UTC... 
THEN START TO MOVE BACK OUT TO SEA AS A COLD FRONT THEREAFTER 
DUE TO A SECONDARY PUSH WITH UPPER LEVEL SUPPORT. ALSO EXPECT 
OVER THE NEXT 24 HOURS FOR SOUTHERLY RETURN FLOW TO REMAIN OVER 
THE CENTRAL AND NE GULF WITH SHOWERS.   

CARIBBEAN SEA...
A TIGHT SURFACE PRESSURE GRADIENT IS OVER THE CARIBBEAN SEA. A 
GALE IS OFF THE COAST OF N COLOMBIA FROM 11N-15N BETWEEN 
71W-79W. 20-30 KT TRADEWINDS ARE OVER THE REMAINDER OF THE 
CARIBBEAN SEA. A MONSOON TROUGH EXTENDS FROM N COLOMBIA TO COSTA 
RICA. ISOLATED MODERATE CONVECTION IS OVER THE SE CARIBBEAN AND 
NICARAGUA FROM 9N-13N BETWEEN 81W-85W. PATCHES OF BROKEN TO 
OVERCAST LOW CLOUDS WITH ISOLATED SHOWERS DOTS THE NW CARIBBEAN 
W OF 80W...AND THE E CARIBBEAN E OF 70W. EXPECT OVER THE NEXT 24 
HOURS FOR MORE SHOWERS TO ADVECT FROM THE ATLANTIC TO THE 
WINDWARD ISLANDS AND N VENEZUELA. ALSO EXPECT CONTINUED RAIN AND 
SHOWERS OVER THE SW CARIBBEAN AND CENTRAL AMERICA.  

ATLANTIC OCEAN...
A 1029 MB HIGH IS CENTERED OVER THE W ATLANTIC NEAR 31N63W. A 
QUASI-STATIONARY FRONT IS OVER THE CENTRAL ATLANTIC FROM 30N37W 
TO 23N42W. WIDELY SCATTERED MODERATE CONVECTION IS WITHIN 60 NM 
E OF THE FRONT. RESIDUAL SHOWERS ARE E OF THE LESSER ANTILLES 
FROM 8N-13N BETWEEN 55W-60W MOVING W. A 1035 MB HIGH IS CENTERED 
W OF SPAIN AT 38N15W. A RIDGE AXIS EXTENDS S FROM THE HIGH TO 
22N20W. EXPECT THE FRONT TO REMAIN QUASI-STATIONARY OVER THE 
NEXT 24 HOURS WITH CONVECTION.

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

$$
FORMOSA