000
AXNT20 KNHC 292317
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST TUE NOV 29 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2315 UTC.

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

THE MONSOON TROUGH EXTENDS ACROSS SW AFRICA AND REACHES GUINEA 
NEAR 10N14W. THE ITCZ CONTINUES TO 8N20W TO 8N40W TO 11N55W. 
WIDELY SCATTERED MODERATE CONVECTION IS FROM 3N-9N BETWEEN 
18W-44W ...AND FROM 6N-11N BETWEEN 44W-50W.

...DISCUSSION...

THE GULF OF MEXICO...
15-20 KT NW FLOW IS OVER THE GULF OF MEXICO AS A COLD FRONT 
EXITS TO THE W ATLANTIC AND NW CARIBBEAN. SCATTERED COLD AIR 
STRATOCUMULUS CLOUDS ARE OVER THE SE GULF AND THE YUCATAN 
PENINSULA. FAIR WEATHER IS ELSEWHERE. COLD AIR ADVECTION 
PERSISTS OVER THE N GULF N OF 24N. IN THE UPPER LEVELS ZONAL 
FLOW IS NOTED WITH STRONG SUBSIDENCE. EXPECT OVER THE THE NEXT 
24 HOURS FOR LITTLE CHANGE. 
 
THE CARIBBEAN SEA...
A COLD FRONT EXTENDS FROM CENTRAL CUBA AT 23N79W TO NICARAGUA AT 
13N83W. BROKEN TO OVERCAST LOW CLOUDS ARE N OF THE FRONT OVER 
THE NW CARIBBEAN AND HONDURAS. SCATTERED SHOWERS ARE WITHIN 30 
NM OF THE FRONT. THE MONSOON TROUGH EXTENDS FROM N COLOMBIA TO 
COSTA RICA. ISOLATED MODERATE CONVECTION IS FROM 7N-11N BETWEEN 
75W-82W. FURTHER N...SCATTERED SHOWERS ARE OVER THE HIGHER 
ELEVATIONS OF HISPANIOLA. ELSEWHERE...A SURFACE TROUGH EXTENDS 
FROM THE LEEWARD ISLANDS AT 20N62W TO VENEZUELA AT 9N64W. 
SCATTERED MODERATE TO STRONG CONVECTION IS INLAND OVER VENEZUELA 
FROM 5N-11N BETWEEN 61W-69W. SCATTERED MODERATE TO ISOLATED 
STRONG CONVECTION IS E OF THE TROUGH AXIS FROM 14N-18N E OF 61W. 
IN THE UPPER LEVELS...A LARGE UPPER LEVEL HIGH IS CENTERED OVER 
COSTA RICA. AN UPPER LEVEL TROUGH IS OVER THE E CARIBBEAN E OF 
70W. STRONG SUBSIDENCE COVERS MOST OF THE CARIBBEAN EXCEPT OVER 
THE WINDWARD ISLANDS. EXPECT...FOR THE COLD FRONT TO DRIFT E 
OVER THE NEXT 24 HOURS...AND THE SURFACE TROUGH OVER THE E 
CARIBBEAN TO MOVE NE AS A 1005 MB LOW DEVELOPS NE OF THE LEEWARD 
ISLANDS NEAR 21N58W.     

THE ATLANTIC OCEAN...
A COLD FRONT IS OVER THE W ATLANTIC FROM 30N76W TO CENTRAL CUBA 
AT 23N79W. SCATTERED SHOWERS ARE WITHIN 30 NM OF THE FRONT. A 
1026 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 36N48W. A 1025 MB 
HIGH IS OVER THE E ATLANTIC NEAR THE MADEIRA ISLANDS AT 33N19W. 
IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED S OF 
BERMUDA AT 27N65W WITH TROUGH AXIS EXTENDING S TO THE E 
CARIBBEAN. UPPER LEVEL DIFFLUENCE E OF THE LOW CENTER IS 
PRODUCING SCATTERED MODERATE TO ISOLATED STRONG CONVECTION FROM 
14N-25N BETWEEN 54W-60W. EXPECT...FOR THE COLD FRONT TO MOVE E 
OVER THE NEXT 24 HOURS WITH SHOWERS. ALSO EXPECT CONTINUED 
CONVECTION NE OF THE LEEWARD ISLANDS DUE TO THE FORMING SURFACE 
LOW AND UPPER LEVEL DIFFLUENCE.   

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

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FORMOSA