000 AXNT20 KNHC 031753 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...ITCZ... ITCZ AXIS IS ANALYZED ALONG 6N10W 3N20W CROSSING THE EQUATOR NEAR 27W CONTINUING S OF THE EQUATOR TO INLAND OVER SOUTH AMERICA. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 2N-11N BETWEEN 9W-14W...AND FROM 5S-4N BETWEEN 26W-28W. SCATTERED MODERATE/STRONG CONVECTION IS FROM THE EQUATOR TO 3N BETWEEN 14W-19W. ...DISCUSSION... GULF OF MEXICO... A DEEP LAYERED TROUGH IS INLAND OVER THE CENTRAL PLAIN STATES SUPPORTING A COLD FRONT THAT AT 03/1500 UTC EXTENDS FROM SOUTHERN MISSISSIPPI COAST NEAR 30N89W ACROSS SE LOUISIANA INTO THE W GULF OF MEXICO NEAR 29N90W ALONG 26N94W INTO THE W BAY OF CAMPECHE NEAR 19N95W AND INLAND OVER MEXICO. ISOLATED SHOWERS ARE WITHIN 30 NM EITHER SIDE OF THE FRONT N OF 23N. SCATTERED SHOWERS ARE WITHIN 30 NM ALONG A LINE FROM 29N92W TO 25N97W W OF THE FRONT. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 90 NM OF THE FRONT S OF 23N BROAD UPPER RIDGE ANCHORED IN THE E PACIFIC REGION EXTENDS AN AXIS N ACROSS S MEXICO AND THE BAY OF CAMPECHE INTO THE GULF OF MEXICO TO SE LOUISIANA AND A SHORTWAVE UPPER TROUGH OVER THE W CARIBBEAN GIVING THE GULF W-NW FLOW. MOSTLY DRY STABLE AIR IS OVER THE E GULF BASIN GIVING MOST OF THE REMAINDER OF THE AREA CLEAR SKIES THIS AFTERNOON. THE COLD FRONT WILL MOVE TO FLORIDA BIG BEND TO BAY OF CAMPECHE TONIGHT AND FROM SW FLORIDA TO EASTERN BAY OF CAMPECHE WED...THEN BEGIN TO DISSIPATE OVER THE SE GULF THU. CARIBBEAN SEA... A SHORTWAVE UPPER TROUGH COVERS THE W CARIBBEAN W OF 74W CENTERED ALONG AN AXIS FROM CENTRAL CUBA TO N NICARAGUA. WATER VAPOR SATELLITE IMAGERY SHOWS DRY STABLE AIR ALOFT W OF 74W. A SE/NW UPPER RIDGE EXTENDS ACROSS THE TROPICAL ATLC TO OVER THE REMAINDER OF THE CARIBBEAN E OF 74W. AREAS OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE BETWEEN SE CUBA AND JAMAICA FROM 18N-20N BETWEEN 73W-79W AND WITHIN 120 NM OF THE COASTS OF W PANAMA AND COSTA RICA. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE E COAST OF HONDURAS. THE SURFACE RIDGE OVER THE W ATLC IS PROVIDING A TIGHTER PRESSURE GRADIENT TO GENERATE MODERATE TO FRESH EASTERLY TRADE WINDS ACROSS THE BASIN. REMNANT LOW LEVEL MOISTURE REMAINS OVER THE CARIBBEAN E OF 75W AND COUPLED WITH THE CONVERGENCE OF THE WINDS AT THE SURFACE AND ALOFT ARE GENERATING SCATTERED SHOWERS MAINLY WITHIN 120 NM OF A LINE FROM THE WINDWARD ISLANDS NEAR 13N61W TO 16N72W. THE REMAINDER OF THE AREA IS UNDER FAIR WEATHER CONDITIONS THIS AFTERNOON. SURFACE RIDGE OVER THE W ATLC WILL CONTINUE TO BUILD S ACROSS THE BAHAMAS AND NW CARIBBEAN AND MAINTAIN FRESH TRADES OVER THE CENTRAL AND W CARIBBEAN. ATLANTIC OCEAN... THE W ATLC IS DOMINATED BY SURFACE RIDGING AND CLEARING SKIES FROM A 1024 MB HIGH N OF THE AREA NEAR 33N71W. AN UPPER LOW COVERS THE CENTRAL TO W ATLC BETWEEN 47W-65W N OF 28N SUPPORTING A WEAKENING COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 32N49W ALONG 28N52W TO 24N58W WITH SCATTERED SHOWERS WITHIN 75 NM E OF THE FRONT. A BROAD SURFACE RIDGE DOMINATES THE REMAINDER OF THE CENTRAL AND E ATLC N OF 10N E OF THE ABOVE FRONT ANCHORED BY A 1022 MB HIGH N OF THE AREA NEAR 33N30W LEAVING THE REMAINDER OF THE ATLC WITH FAIR WEATHER THIS AFTERNOON. SURFACE RIDGE OVER THE W ATLC WILL CONTINUE TO BUILD S ACROSS THE BAHAMAS INTO THE NW CARIBBEAN AND SHIFT E AS THE NEXT COLD FRONT MOVES OFF THE SE U.S. COAST WED MORNING AND MOVING W TO JUST W OF BERMUDA TO STRAITS OF FLORIDA THU THEN DISSIPATE BY FRI. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MONTALVO/WALTON