000 AXNT20 KNHC 020541 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT WED MAY 02 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 10N15W TO 06N16W TO 03N21W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 03N21W TO THE EQUATOR NEAR 37W. SCATTERED MODERATE CONVECTION IS FROM 01N-07N BETWEEN 09W-17W. ...DISCUSSION... GULF OF MEXICO... WESTERLY UPPER LEVEL FLOW DOMINATES ACROSS THE GULF BASIN THIS EVENING...HOWEVER A WEAK MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH IS NOTED ON WATER VAPOR IMAGERY PROGRESSING ACROSS THE LOWER MISSISSIPPI RIVER VALLEY. THIS SHORTWAVE IS EXPECTED TO MOVE E-NE OVER THE NEXT 24 TO 36 HOURS AND INFLUENCE THE MOVEMENT OF A SURFACE TROUGH...ANALYZED OVER THE CENTRAL GULF FROM 29N86W TO 24N90W...TO THE NORTH-NORTHWEST AS IT CONTINUES TO WEAKEN GRADUALLY. LOW-LEVEL MOISTURE CONVERGENCE IN THE VICINITY OF THE SURFACE TROUGH ALONG WITH THE APPROACHING MIDDLE TO UPPER LEVEL SUPPORT WILL AID IN GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING CURRENTLY FROM 26N-29N BETWEEN 84W-92W. GLOBAL MODEL GUIDANCE INDICATES THE MOISTURE AND PRECIPITATION WILL MOVE NORTHWARD AND WEAKEN ON WEDNESDAY ACROSS THE NORTH-CENTRAL GULF WATERS AND COASTAL PLAINS. MOSTLY E-SE WINDS IN THE RANGE OF 10 TO 20 KT ARE EXPECTED OVER THE REMAINDER OF THE BASIN WITH THE STRONGEST WINDS ANTICIPATED OVER THE EASTERN GULF E OF 87W AND THE FLORIDA STRAITS AS THE PRESSURE GRADIENT REMAINS STRONGEST BETWEEN THE SURFACE TROUGHING AND HIGH PRESSURE OVER THE SW NORTH ATLC. CARIBBEAN SEA... SOUTHWEST TO WEST UPPER LEVEL FLOW IS NOTED ACROSS THE CARIBBEAN THIS EVENING AS WATER VAPOR IMAGERY INDICATES THAT MUCH OF THE NW CARIBBEAN IS UNDER THE INFLUENCE OF MODERATELY DRY AIR ALOFT. ELSEWHERE S OF 16N W OF 80W...UPPER LEVEL MOISTURE AND HIGH LEVEL CLOUDINESS IS NOTED STREAMING NORTH-NORTHEASTWARD NORTH OF AN UPPER LEVEL DIFFLUENT REGION ALONG 10N IN THE VICINITY OF UPPER LEVEL RIDGING. LOW-LEVEL MOISTURE IS HOWEVER PRESENT OVER TWO NOTABLE AREAS OF THE CARIBBEAN. THE FIRST AREA IS LOW-LEVEL MOISTURE CONVERGENCE ASSOCIATED WITH THE REMNANTS OF MID-LEVEL TROUGHING ACROSS THE SW NORTH ATLC. MID-LEVEL MOISTURE IS PREVALENT OVER THE GREATER ANTILLES AND CONTINUES TO GENERATE WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS N OF 18N BETWEEN 68W-84W...INCLUDING HISPANIOLA...CUBA...AND THE WINDWARD PASSAGE. THE OTHER AREA OF LOW-LEVEL MOISTURE BEGINNING TO MERGE WITH THE PREVIOUSLY MENTIONED AREA IS VERY WEAK TROUGHING ACROSS THE EASTERN CARIBBEAN EMBEDDED WITHIN THE EASTERLY TRADE FLOW. ISOLATED SHOWERS ARE OCCURRING FROM 15N-20N BETWEEN 53W-68W... INCLUDING PUERTO RICO AND THE LEEWARD ISLANDS. OTHERWISE... MODERATE TO FRESH EASTERLY TRADES ARE EXPECTED TO PERSIST THROUGH THURSDAY THEN BEGIN TO GRADUALLY DIMINISH BY THE WEEKEND. ATLANTIC OCEAN... WEAK MID-LEVEL TROUGHING IS NOTED ON WATER VAPOR IMAGERY OVER THE SW NORTH ATLC IN THE VICINITY OF 25N72W. THIS SYSTEM HAS MOVED FROM THE NW CARIBBEAN TO THE FLORIDA STRAITS AND NOW INTO THE SW NORTH ATLC OVER THE PAST SEVERAL DAYS AND CONTINUES TO GENERATE A LARGE AREA OF WIDELY SCATTERED SHOWERS FROM 21N-29N BETWEEN 64W-72W...WITH ISOLATED SHOWERS ELSEWHERE S OF 26N W OF 64W. THIS ACTIVITY SPREADS SOUTHWESTWARD ACROSS THE GREATER ANTILLES AND INTO THE NORTH-CENTRAL CARIBBEAN AS WELL. AT THE SURFACE AND PRIMARILY TO THE NORTH OF THIS ACTIVE WEATHER...A 1025 MB HIGH IS CENTERED OVER BERMUDA NEAR 33N64W AND EXTENDS A RIDGE AXIS ALONG 32N TO THE GEORGIA COAST NEAR SAVANNAH. FARTHER EAST...AN UPPER LEVEL TROUGH AXIS EXTENDS INTO THE DISCUSSION AREA NEAR 32N45W TO 26N54W AND SUPPORTS A COLD FRONT FROM 32N46W TO 29N50W TO 28N56W AND BEGINS DISSIPATING TO 29N65W. ISOLATED SHOWERS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF THE FRONT. A SURFACE TROUGH IS LOCATED TO THE SE OF THE FRONT ANALYZED FROM 30N48W TO 23N51W. POSSIBLE ISOLATED SHOWERS ARE OCCURRING WITHIN 75 NM EITHER SIDE OF THE TROUGH AXIS. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1024 MB HIGH CENTERED NEAR 30N36W THAT IS FORECAST TO DRIFT SOUTHEASTWARD OVER THE NEXT 24 TO 36 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN