000 AXNT20 KNHC 142357 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON MAY 14 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. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA TO THE COAST OF GUINEA AT 11N15W CROSSING INTO THE E ATLC TO 6N24W. THE ITCZ CONTINUES FROM 6N24W ALONG 4N37W TO THE NRN COAST OF BRAZIL AT 3N51W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 6N-8N BETWEEN 14W-21W. ...DISCUSSION... THE GULF OF MEXICO... MAINLY WSWLY FLOW ALOFT COVERS THE GULF OF MEXICO THIS EVENING WITH DRY AIR COVERING THE NW CORNER AND MOIST AIR COVERING THE REMAINDER OF THE BASIN. AT THE SURFACE...A STATIONARY FRONT EXTENDS FROM THE FLORIDA PANHANDLE AT 31N85W TO THE BAY OF CAMPECHE ALONG 27N87W 23N92W 18N92W...AS OF 2100 UTC. CLUSTERS OF SHOWERS/THUNDERSTORMS LIE MAINLY E OF THE BOUNDARY COVERING THE E AND SE GULF INCLUDING THE YUCATAN PENINSULA...THE FLORIDA PENINSULA AND WRN CUBA. SHOWERS/THUNDERSTORMS ALSO EXTEND 75 NM W OF THE AXIS.S THE NW GULF IS MAINLY DRY DUE TO THE DRY AIR ALOFT AND INFLUENCED BY SURFACE RIDGING TO THE N. THE FRONT IS SUPPORTED BY AN UPPER LEVEL SHORTWAVE TROUGH THAT IS CURRENTLY ACROSS GEORGIA. SINCE THE MAIN SUPPORT FOR THE FRONT HAS MOVED TO THE E...THE BOUNDARY WILL REMAIN STATIONARY UNTIL A LONGWAVE UPPER TROUGH APPROACHES THE BASIN FROM THE W AND WILL MOVE THE BOUNDARY EWD AS A COLD FRONT. SHOWERS/THUNDERSTORMS WILL LIKELY REMAIN OVER THE ERN GULF. THE CARIBBEAN SEA... SHOWERS/THUNDERSTORMS ARE IMPACTING MOST OF THE NRN CARIBBEAN ISLANDS INCLUDING CUBA...HISPANIOLA...AND PUERTO RICO. THIS IS LIKELY ATTRIBUTED TO DAYTIME HEATING COMBINED WITH LOW-LEVEL MOISTURE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE ALSO ACROSS THE NW GULF. A SURFACE TROUGH HAS BEEN MOVING THROUGH THE SW CARIBBEAN AND CURRENTLY IS PARALLEL TO NICARAGUA AND COSTA RICA ALONG 16N82W 9N82W. SURFACE CONVERGENCE IN COMBINATION WITH AMPLE MOISTURE AND INFLUENCE FROM THE E PACIFIC MONSOON TROUGH...IS HELPING PRODUCE STRONG SHOWERS/THUNDERSTORMS ACROSS MUCH OF NRN PANAMA AND COSTA RICA WITH MORE SCATTERED ACTIVITY ACROSS NICARAGUA AND HONDURAS. THE TROUGH IS EXPECTED TO MOVE WWD INTO CENTRAL AMERICA AND WILL CONTINUE TO PRODUCE HEAVY RAIN ACROSS PORTIONS OF CENTRAL AMERICA. THE CENTRAL AND ERN CARIBBEAN ARE EXPERIENCING MOSTLY FAIR CONDITIONS BESIDES THE SHOWERS MENTIONED ACROSS THE NRN ISLANDS. TRADEWIND FLOW OF 15-20 KTS IS PRESENT. SOME UPPER LEVEL MOISTURE IS SPREADING OVER THE LESSER ANTILLES AROUND AN UPPER LEVEL TROUGH ALONG 67W. EXPECT MOIST CONDITIONS TO REMAIN OVER THE SW GULF FOR THE NEXT COUPLE OF DAYS. THE ATLANTIC OCEAN... WHILE SURFACE RIDGING IS COVERING THE FAR W ATLC...MOISTURE AND ASSOCIATED SHOWERS AND ISOLATED THUNDERSTORMS COVER THE AREA W OF 74W INCLUDING THE WRN BAHAMAS AND FLORIDA. THIS IS ASSOCIATED WITH MOIST SWLY FLOW ALOFT AROUND THE E SIDE OF A SHORTWAVE TROUGH MOVING ACROSS GEORGIA AND SOUTH CAROLINA. THE NW ATLC IS COVERED BY AN UPPER LEVEL RIDGE ALONG 63W SUPPORTING THE SURFACE RIDGE. HOWEVER... AN UPPER LEVEL TROUGH TO THE S ALONG 66W SUPPORTS A WEAK 1022 MB SURFACE LOW NEAR 32N58W. A STATIONARY FRONT ASSOCIATED WITH THE SYSTEM IS ALONG 31N55W 29N56W 27N64W. SCATTERED SHOWERS ARE WITHIN 45 NM EITHER SIDE OF THE AXIS. FARTHER S...TWO SURFACE TROUGHS ARE PRODUCING SHOWERS AND POSSIBLE THUNDERSTORMS. THE FIRST IS N OF THE VIRGIN ISLANDS ALONG 23N65W TO 18N65W. SCATTERED SHOWERS ARE WITHIN 160 NM TO THE E. THE SECOND TROUGH IS E OF THE LESSER ANTILLES ALONG 19N55W TO 15N55W SUPPORTING SCATTERED SHOWERS WITHIN 160 NM EITHER SIDE OF THE AXIS. THE REMAINDER OF THE BASIN IS INFLUENCED BY SURFACE RIDGING EXTENDING FROM THE CENTRAL ATLC. ALOFT...AN UPPER LEVEL TROUGH EXTENDS FROM THE AZORES ISLANDS TO NEAR 28N59W. AN UPPER LEVEL RIDGE COVERS THE TROPICAL ATLC CENTERED NEAR 8N38W PROVIDING FAIR CONDITIONS ACROSS THE ERN TROPICAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORMOSA