000 AXNT20 KNHC 032358 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU MAY 03 2012 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. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 11N15W TO 4N17W WHERE THE ITCZ AXIS CONTINUES ALONG 4N26N 3N33W TO SOUTH AMERICA NEAR 2N51W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 1N TO INLAND OVER AFRICA E OF 3W ACROSS THE PRIME MERIDIAN. CLUSTERS OF SCATTERED MODERATE/ ISOLATED STRONG CONVECTION ARE FROM 5N TO THE EQUATOR BETWEEN 27W-40W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 5N-9N BETWEEN 48W-61W INCLUDING PORTIONS OF SOUTH AMERICA. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE EXTENDS FROM S MEXICO AND THE BAY OF CAMPECHE TO THE N GULF COAST NEAR THE LOUISIANA/TEXAS BORDER. THE MID/UPPER LEVEL SHORTWAVE TROUGH EXTENDS FROM THE MIDDLE MISSISSIPPI VALLEY INTO THE GULF OVER THE FAR W FLORIDA PENINSULA TO ACROSS THE E GULF TO W TIP OF CUBA SUPPORTING A SURFACE TROUGH THAT DEVELOPED AT 03/2100 UTC ALONG 86W FROM 27N-30N AND A WELL DEFINED MID LEVEL CYCLONIC CENTER OBSERVED ON VISIBLE SATELLITE IMAGERY NEAR 28N85W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 90 NM OF LINE FROM W CUBA NEAR 23N83W TO INLAND OVER THE FLORIDA PANHANDLE NEAR APALACHICOLA. A WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC OVER THE FLORIDA PENINSULA AND OVER THE N GULF COAST STATES TO MISSISSIPPI. THE REMAINDER OF THE GULF IS UNDER CLEAR SKIES THIS EVENING. HIGH PRESSURE WILL BUILD W FRI THROUGH THE WEEKEND WITH RIDGE EXTENDING FROM THE W ATLC ACROSS N GULF COAST. CARIBBEAN SEA... SW TO W FLOW ALOFT DOMINATES THE CARIBBEAN BASIN. A SURFACE TROUGH EXTENDS FROM 21N62W INTO THE CARIBBEAN BETWEEN THE VIRGIN ISLANDS AND PUERTO RICO GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 16N-21N BETWEEN 59W-71W INCLUDING THE ISLANDS FROM THE LEEWARD ISLANDS TO THE DOMINICAN REPUBLIC. AFTERNOON THUNDERSTORMS HAVE DEVELOPED ACROSS CUBA AND HAITI AND COULD PRODUCE ISOLATED SHOWERS/THUNDERSTORMS ALONG THE IMMEDIATE COASTLINES. AFTERNOON THUNDERSTORMS HAVE ALSO DEVELOPED INLAND OVER VENEZUELA. THE SW FLOW ALOFT OVER THE S CARIBBEAN IS DRAWING THE TROPICAL MOISTURE INTO THE S CARIBBEAN WATERS WITH ISOLATED SHOWERS/THUNDERSTORMS WITHIN 90 NM ALONG THE COAST. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN UNDER MOSTLY CLEAR SKIES THIS EVENING. SURFACE TROUGH OVER NE CARIBBEAN WILL DRIFT W THROUGH MON. OTHERWISE WEAK HIGH PRESSURE OVER W ATLC WILL GIVE THE CARIBBEAN GENTLE TO MODERATE BREEZE ACROSS BASIN THROUGH TUE. ATLANTIC OCEAN... A SURFACE RIDGE DOMINATES THE W ATLC AND INTO THE CENTRAL ATLC ANCHORED BY A 1022 MB HIGH NEAR 28N76W EXTENDING NW TO OVER THE N COAST OF THE GULF OF MEXICO. A LARGE UPPER LOW OFF THE CANADIAN MARITIMES IS SUPPORTING A COLD FRONT THAT IS ALONG THE N PERIPHERY OF THE DISCUSSION AREA EXTENDING THROUGH 32N59W S OF BERMUDA NEAR 31N65W TO BEYOND 32N71W. A WEAK UPPER TROUGH IS IN THE CENTRAL ATLC FROM 32N46W TO NEAR 24N51W SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 30N45W TO 24N52W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 120 NM E OF THE TROUGH. A SECOND SURFACE RIDGE DOMINATES THE E ATLC ANCHORED BY A 1021 MB HIGH NEAR 27N28W. A SURFACE TROUGH EXTENDS FROM 21N62W INTO THE CARIBBEAN BETWEEN THE VIRGIN ISLANDS AND PUERTO RICO GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS S OF 21N BETWEEN 59W-71W INCLUDING ISLANDS FROM THE LEEWARD ISLANDS TO THE DOMINICAN REPUBLIC. THE COLD FRONT ALONG 31N WILL CONTINUE S AND STALL ALONG 25N E OF 70W FRI NIGHT AND DISSIPATE SAT. W ATLC SURFACE HIGH WILL SHIFT S FRI REACHING NW BAHAMAS THEN BECOME DIFFUSE SAT WITH A RIDGE EXTENDING FROM THE E GULF OF MEXICO ACROSS FLORIDA TO THE CENTRAL BAHAMAS. STRONGER COLD FRONT WILL ENTER THE W ATLC SAT EXTENDING FROM BERMUDA TO NW BAHAMAS SUN AND ACROSS SE BAHAMAS MON AND TUE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW