000 AXNT20 KNHC 010541 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE MAY 01 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N13W TO 05N15W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 05N15W TO 03N25W TO 01N33W TO THE EQUATOR NEAR 50W. ISOLATED MODERATE CONVECTION IS FROM 01N-06N BETWEEN 25W-32W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH EXTENDS FROM NORTHERN FLORIDA TO THE FLORIDA STRAITS AND CONTINUES TO GRADUALLY WEAKEN. WITH THE UPPER LEVEL TROUGHING SLOWLY DRIFTING NORTH-NORTHEAST INTO THE SW NORTH ATLC...A SURFACE TROUGH...ANALYZED FROM 25N83W TO 19N84W...CONTINUES TO DISTANCE ITSELF FROM THE UPPER LEVEL FEATURE AND DRIFT WESTWARD INTO THE SOUTH-CENTRAL GULF. GLOBAL MODEL GUIDANCE HAS CONSISTENTLY SUGGESTED THIS SURFACE TROUGH WILL MOVE NORTHWEST AND WEAKEN OVER THE CENTRAL GULF ON WEDNESDAY. IN THE MEANTIME...LOW-LEVEL MOISTURE CONVERGENCE IN THE VICINITY OF THE SURFACE TROUGH IS GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS FROM 23N-26N W OF 87W...INCLUDING PORTIONS OF THE SOUTHERN FLORIDA PENINSULA...THE FLORIDA STRAITS...AND THE FLORIDA KEYS. THE REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF WESTERLY FLOW ALOFT AND A SURFACE RIDGE ANCHORED BY A 1018 MB HIGH CENTERED OVER CENTRAL ALABAMA. THE RIDGE AXIS EXTENDS FROM NORTHERN FLORIDA NEAR 30N83W TO 28N92W TO THE MEXICO COAST NEAR 22N98W. GENERALLY EAST TO SOUTHEAST WINDS IN THE RANGE OF 15 TO 25 KT ARE OBSERVED ACROSS THE GULF THIS EVENING...WITH THE STRONGEST WINDS CONCENTRATED NEAR THE NORTHERN PORTION OF THE SURFACE TROUGH FROM 24N-28N W OF 90W. CARIBBEAN SEA... WEST TO SOUTHWESTERLY UPPER LEVEL FLOW IS NOTED ACROSS THE CARIBBEAN THIS EVENING AS WATER VAPOR IMAGERY INDICATES THAT MUCH OF THE BASIN IS UNDER THE INFLUENCE OF MODERATELY DRY AIR ALOFT. LOW-LEVEL MOISTURE IS HOWEVER PRESENT AND ADVECTING OVER TWO AREAS OF THE CARIBBEAN. THE FIRST AREA IS LOW-LEVEL MOISTURE CONVERGENCE ASSOCIATED WITH A SURFACE TROUGH ANALYZED FROM THE SE GULF OF MEXICO NEAR 25N83W TO 19N84W IN THE NW CARIBBEAN. MUCH OF THE CONVERGENCE IS EAST-SOUTHEAST OF THE SURFACE TROUGH AND CONTINUES TO GENERATE WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE SW NORTH ATLC REGION AS WELL AS THE NORTH-CENTRAL CARIBBEAN WATERS N OF 17N BETWEEN 66W-83W. THE SURFACE TROUGH IS FORECAST TO DRIFT NORTHWESTWARD AND GRADUALLY DISSIPATE BY WEDNESDAY OVER THE CENTRAL GULF OF MEXICO. THE OTHER AREA OF LOW-LEVEL MOISTURE IS LOCATED OVER THE EASTERN CARIBBEAN PRODUCING ISOLATED SHOWERS FROM 12N-19N BETWEEN 59W-66W... INCLUDING THE LESSER ANTILLES. OTHERWISE...MODERATE TO FRESH EASTERLY TRADES ARE EXPECTED TO PERSIST THROUGH FRIDAY. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH EXTENDS ALONG THE SPINE OF THE FLORIDA PENINSULA AND IS PROVIDING MOST OF THE SW NORTH ATLC WITH PLENTY OF MOISTURE AND OVERCAST CLOUDINESS W OF 70W. INFRARED SATELLITE IMAGERY INDICATES THAT SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING OVER A LARGE AREA FROM 20N-29N BETWEEN 71W-81W. TO THE NORTHEAST OF THIS AREA... UPPER LEVEL TROUGHING DIPS SOUTHWARD FROM THE CANADIAN MARITIMES ALONG 55W AND SUPPORTS A WEAK COLD FRONT ANALYZED ALONG 32N56W TO 30N72W. ISOLATED SHOWERS ARE OCCURRING WITHIN 75 NM EITHER SIDE OF THE FRONT. OTHERWISE THE REMAINDER OF THE CENTRAL AND EASTERN ATLC ARE UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1030 MB HIGH CENTERED N-NW OF THE AZORES NEAR 43N33W. A WEAK SURFACE TROUGH IS EMBEDDED WITHIN THE SOUTHWESTERN PERIPHERY OF THE RIDGING AND IS ANALYZED FROM 27N52W TO 23N51W. LOW-LEVEL MOISTURE CONVERGENCE IN THE VICINITY OF THE TROUGH AXIS IS GENERATING ISOLATED SHOWERS FROM 22N-28N BETWEEN 46W-57W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN