000
AXNT20 KNHC 031048
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
805 AM EDT TUE MAY 03 2011

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1015 UTC.

...ITCZ...

THE ITCZ AXIS EXTENDS FROM THE COAST OF LIBERIA NEAR 6N10W...S 
WESTWARD ALONG 5N20W 2N30W INTO NE BRAZIL NEAR 2S42W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION IS NEAR THE COAST OF 
BRAZIL FROM 5S-10S W OF 30W. A BROAD AREA OF MODERATE TO 
ISOLATED STRONG CONVECTION ASSOCIATED TO A MESOSCALE CONVECTIVE 
SYSTEM IS MOVING OUT OF WEST AFRICA THROUGH LIBERIA AND COTE 
D'IVOIRE E OF 12W.

...DISCUSSION...

GULF OF MEXICO...
AN UPPER LEVEL TROUGH MOVES ACROSS THE CENTRAL CONUS THIS 
MORNING. A SHORT WAVE ASSOCIATED WITH THE UPPER TROUGH MOVES 
ACROSS EAST TEXAS SUPPORTING A COLD FRONT THAT EXTENDS ACROSS 
THE SE STATES AND ENTERS THE GULF OF MEXICO THROUGH CENTRAL 
LOUISIANA NEAR 30N91W CONTINUING SSE TO VERACRUZ MEXICO ALONG 
25N94W 19N95W. SCATTERED MODERATE TO HEAVY SHOWERS AND ISOLATED 
THUNDERSTORMS ARE ALONG AND W OF THE BOUNDARY N OF 24N. 
SCATTERED SHOWERS ARE BEGINNING TO DEVELOP OVER THE BAY OF 
CAMPECHE S OF 22N E OF 94W AS WEAK TROUGHING STRAITS TO DEVELOP 
IN RESPONSE OF THE COMING COLD FRONT. THIS FRONT IS EXPECTED TO 
CONTINUE TO MOVE EASTWARD EXTENDING FROM THE FLORIDA PANHANDLE 
TO THE SOUTHERN BAY OF CAMPECHE WITH CONVECTION OVER THE NEXT 24 
HOURS. MARINE OBSERVATIONS INCLUDING OIL PLATFORMS INDICATE 
GUSTY NORTHERLY WINDS UP TO 30 KT BEHIND THE FRONT GUSTING TO 
NEAR GALE FORCE. SSE WINDS 10-15 KT ARE AHEAD OF THE FRONT 
BRINGING A FEW ISOLATED SHOWERS THROUGH THE FLORIDA STRAITS. 
FAIR WEATHER CONDITIONS ARE E OF THE FRONT AS WELL...DUE TO 
STRONG SUBSIDENCE AND DRY AIR ALOFT NOTED ON WATER VAPOR 
IMAGERY.   

CARIBBEAN SEA...
SCATTERED MODERATE TO HEAVY SHOWERS AND THUNDERSTORMS COVER THE 
CARIBBEAN E OF A LINE FROM 18N76W TO 15N71W TO 11N67W ALSO 
INCLUDING THE LESSER ANTILLES. WITHIN THIS REGION OF ACTIVE 
WEATHER...A SURFACE TROUGH IS MOVING ACROSS EASTERN 
HISPANIOLA...WITH AXIS ANALYZED FROM 20N68W TO 14N70W. THE 
TROUGH AXIS LACKS OF CYCLONIC CURVATURE AT SURFACE...WHICH IS 
BETTER DEPICTED ON THE 700 MB STREAMLINE GFS MODEL ANALYSIS. 
THIS SYSTEMS IS SUPPORTED ALOFT BY A COMBINATION OF A BROAD AREA 
OF DIFFLUENT FLOW ALOFT THAT COVERS THE EASTERN HALF OF THE 
CARIBBEAN SEA AND CLOSE PROXIMITY TO THE ENTRANCE REGION OF AN 
70 KT UPPER LEVEL JET N OF THE DOMINICAN REPUBLIC. THIS AREA OF 
CONVECTION IS EXPECTED TO REMAIN OVER THE EASTERN HALF OF THE 
CARIBBEAN BASIN OVER THE NEXT 24 HOURS...AFFECTING THE COASTAL 
WATERS OVER THE LESSER ANTILLES INCLUDING THE WATERS S OF PUERTO 
RICO. THIS SYSTEM WILL ALSO PRODUCE LOCALLY HEAVY RAINFALL AND 
FLOODING OVER HISPANIOLA. ELSEWHERE ACROSS THE CARIBBEAN W OF 
71W...FRESH TO STRONG EASTERLY TRADE WINDS CONTINUE AND ARE 
EXPECTED TO PERSIST OVER THE NEXT FEW DAYS. THESE TRADES ARE 
BANKING SOME LOW LEVEL MOISTURE AND ISOLATED SHOWERS WITHIN 120 
NM OF THE COAST OF COSTA RICA AND S NICARAGUA WITH THE REMAINDER 
OF THE CARIBBEAN IS EXPERIENCING MOSTLY FAIR WEATHER CONDITIONS.

ATLANTIC OCEAN...
AN UPPER LEVEL TROUGH/CUT-OFF LOW MOVE ACROSS THE CENTRAL ATLC 
SUPPORTING ITS SURFACE REFLECTION...AN OCCLUDED 1006 MB LOW NEAR 
37N55W. A COLD FRONT EXTENDS FROM THIS SYSTEM INTO THE AREA FROM 
32N49W TO 27N52W TO 23N60W. SCATTERED SHOWERS AND THUNDERSTORMS 
ARE OCCURRING WITHIN 50 NM ON EITHER SIDE OF THE FRONT. THE 
FRONT IS FORECAST TO CONTINUE TO TRACK EASTWARD WITH CONVECTION 
OVER THE NEXT 24 HOURS AS THE SURFACE LOW ENTERS OUR DISCUSSION 
AREA NEAR 30N50W. SURFACE RIDGING DOMINATES THE REST OF THE ATLC 
ANCHORED BY A 1025 MB HIGH OVER THE WEST ATLC NEAR 33N71W AND A 
BROAD 1022 MB HIGH OVER THE EAST ATLC NEAR 35N35W. HOWEVER 
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS EXTEND INTO THE 
ATLC S OF 21N BETWEEN 67W-72W FROM THE SURFACE TROUGH MENTIONED 
IN CARIBBEAN SEA DISCUSSION. ALSO SCATTERED SHOWERS AND 
THUNDERSTORMS ARE IN THE WEST TROPICAL ATLC AND INTO THE E 
CARIBBEAN W OF 54W FROM 10N-18N SUPPORTED ALOFT BY A BROAD AREA 
OF DIFFLUENT FLOW. CONVECTION IN THIS REGION IS EXPECTED TO 
LINGER OVER THE NEXT 24 HOURS.  

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

$$

GARCIA