000
AXNT20 KNHC 240546
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT TUE MAR 24 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0515 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 6N11W 3N20W...CROSSING THE EQUATOR 
NEAR 29W...AND INTO NE BRAZIL NEAR 3S40W. ISOLATED MODERATE 
CONVECTION IS WITHIN 90 NM OF THE AXIS BETWEEN 20W-26W. 
 
...DISCUSSION...

GULF OF MEXICO...
AN UPPER LEVEL TROUGH IS ACROSS THE W ATLC AND NW CARIBBEAN SEA 
WITH NW UPPER FLOW DOMINATING ACROSS THE FLORIDA PENINSULA AND 
THE ENTIRE GULF. AT THE SURFACE...A 1025 MB HIGH IS CENTERED IN 
THE W ATLC OFF THE GEORGIA COAST NEAR 31N80W AND IS PROVIDING 
THE GULF WITH MOSTLY FAIR CONDITIONS AND SE RETURN FLOW OF UP TO 
20 KT. THIS RETURN FLOW IS IN RESPONSE TO A DEEP LAYERED TROUGH 
AND CORRESPONDING SURFACE LOW LOCATED OVER THE CENTRAL CONUS. 
OVER THE NEXT 24 HOURS THE RIDGE OF HIGH PRESSURE IS FORECAST TO 
REMAIN ANCHORED IN THE W ATLC WHILE MAINTAINING THE SLY RETURN 
FLOW ACROSS THE GULF AHEAD OF THE NEXT COLD FRONT EXPECTED TO 
CLIP THE EXTREME NW GULF EARLY WED. 
 
CARIBBEAN SEA...
MODERATE TO FRESH TRADE WINDS ARE BLOWING ACROSS THE CARIBBEAN 
SEA WITH LOW-LEVEL CONVERGENCE OF THESE ELY TRADES GENERATING 
ISOLATED SHOWERS ACROSS THE CENTRAL CARIBBEAN...HISPANIOLA AND 
PUERTO RICO. THE STRONGEST OF THESE TRADEWINDS...UP TO 25 KT... 
ARE OBSERVED ALONG THE COAST OF COLOMBIA. AN UPPER TROUGH 
EXTENDS FROM THE W ATLC ACROSS THE NW CARIBBEAN AND IS PROVIDING 
MODERATE TO STRONG SUBSIDENCE NW OF A LINE FROM HISPANIOLA TO 
SRN NICARAGUA. E OF THE TROUGH AXIS...STRONG SWLY UPPER WINDS 
ARE BLOWING AS THE TAIL END OF A 80 TO 100 KT STREAM JET EXTENDS 
FROM ERN NICARAGUA NE ACROSS JAMAICA AND HISPANIOLA INTO THE 
CENTRAL ATLC. UPPER LEVEL MOISTURE IS STREAMING HIGH LEVEL 
CLOUDINESS ACROSS THE ERN CARIBBEAN E OF 77W. ELSEWHERE THE TAIL 
END OF A CENTRAL ATLC COLD FRONT EXTENDS ACROSS ANGUILLA TO NEAR 
17N65W. SCATTERED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE 
FRONT ACROSS THE FAR NE CARIBBEAN AND NRN LEEWARD ISLANDS.
 
ATLANTIC OCEAN...
A DEEP LAYERED TROUGH IS OVER THE NW ATLC AND SUPPORTS A COLD 
FRONT THAT ENTERS THE CENTRAL ATLC DISCUSSION AREA NEAR 32N51W 
EXTENDING ALONG 30N52W 25N56W TO 20N60W AND INTO THE FAR NE 
CARIBBEAN SEA. THIS FRONTAL BOUNDARY ALONG WITH AN AREA OF UPPER 
LEVEL DIFFLUENCE E OF THE UPPER TROUGH IS GENERATING SCATTERED 
SHOWERS WITHIN 250 NM E OF THE COLD FRONT N OF 20N. ACROSS THE W 
ATLC...A 1025 MB HIGH IS CENTERED OFF THE GEORGIA COAST NEAR 
31N80W AND IS PROVIDING THE W ATLC WITH NE TO ELY SURFACE FLOW 
AND BROKEN STRATOCUMULUS CLOUDS WITH EMBEDDED ISOLATED SHOWERS W 
OF 58W. E OF THE FRONTAL BOUNDARY ACROSS THE E ATLC...A RIDGE 
OF HIGH PRESSURE EXTENDS FROM N OF THE AZORES TO ACROSS THE 
TROPICAL ATLC. FAIR WEATHER CONDITIONS AND A FEW PASSING HIGH 
CLOUDS ARE OBSERVED ON SATELLITE IMAGERY UNDER MAINLY 15 TO 20 
KT NE TO E SURFACE FLOW.

$$
HUFFMAN