000 AXNT20 KNHC 270540 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE SEP 27 2011 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 0445 UTC. ...SPECIAL FEATURES... TROPICAL STORM PHILIPPE IS CENTERED NEAR 15.9N 34.8W AT 27/0300 UTC OR ABOUT 620 NM W OF THE CAPE VERDE ISLANDS MOVING NW AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1003 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. PLEASE SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/ WTNT22 KNHC FOR MORE DETAILS. PHILIPPE IS A LITTLE WEAKER AND IT IS EXPECTED TO MOVE INTO AN ENVIRONMENT OF INCREASING SW SHEAR OVER THE NEXT DAY OR SO. NUMEROUS STRONG CONVECTION IS WITHIN A 60 NM RADIUS OF 15.5N34W WITH SCATTERED MODERATE/ISOLATED STRONG CONVECTION COVERING THE REMAINDER OF THE AREA FROM 13N-17N BETWEEN 31W-35W. A 1010 MB LOW...REMNANT LOW OF OPHELIA...IS CURRENTLY CENTERED NE OF THE LEEWARD ISLANDS NEAR 19N59W. SATELLITE IMAGERY INDICATE THAT THE SURFACE CIRCULATION IS GRADUALLY BECOMING BETTER DEFINED AND UPPER LEVEL WINDS APPEAR SOMEWHAT CONDUCIVE FOR ADDITIONAL DEVELOPMENT OF THIS LOW AS IT MOVES SLOWLY NW DURING THE NEXT DAY OR TWO. THIS SYSTEM HAS A HIGH CHANCE OF REGENERATING INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. LOCALLY HEAVY RAINS ARE POSSIBLE OVER PORTIONS OF THE NORTHERN LEEWARD ISLANDS THROUGH WEDNESDAY. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 90 NM OF LINE FROM 15N57W TO 20N59W. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM 16N47W TO 10N46W MOVING W 5-10 KT. WAVE IS WEAKENING AS IT BECOMING LESS DEFINED IN THE UPPER LEVEL SATELLITE WINDS WITH LITTLE CLOUD SIGNATURE ON SATELLITE IMAGERY. ISOLATED SHOWERS ARE POSSIBLE WITHIN 60 NM EITHER SIDE OF THE WAVE AXIS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA ENTERING THE E TROPICAL ATLC NEAR 14N16W TO 13N18W. CLUSTERS OF SCATTERED MODERATE/ ISOLATED STRONG CONVECTION ARE FROM 3N-12N BETWEEN 26W-37W. ...DISCUSSION... GULF OF MEXICO... THE LARGE UPPER LOW REMAINS OVER THE UPPER MISSISSIPPI VALLEY EXTENDING A BROAD UPPER TROUGH INTO THE GULF N OF 25N SUPPORTING A COLD FRONT THAT CURRENTLY IS INLAND STRETCHING FROM NE GEORGIA ACROSS ALABAMA AND MISSISSIPPI TO CENTRAL LOUISIANA BECOMING STATIONARY ACROSS TEXAS. A SURFACE TROUGH REMAINS OVER THE E GULF EXTENDING AT 27/0300 UTC FROM SW GEORGIA ACROSS THE FLORIDA PANHANDLE NEAR TALLAHASSEE ALONG 29N84W TO FLORIDA BAY NEAR 25N82W. A BROAD UPPER RIDGE COVERS THE S GULF ANCHORED OVER S MEXICO. THE FINAL RESULT IS NEAR WESTERLY FLOW ALOFT ACROSS THE GULF. STRONG SUBSIDENCE AND DRY STABLE AIR DOMINATES THE N OF GULF WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE SE GULF S OF 26N E OF 90W TO ACROSS S FLORIDA AND THROUGH THE STRAITS OF FLORIDA. A WEAK HIGH PRESSURE COVERS THE GULF W OF THE SURFACE TROUGH WITH THE REMAINDER OF THE GULF UNDER CLEAR SKIES TONIGHT. WEAK HIGH PRESSURE WILL PERSIST TONIGHT THROUGH THU. A SECOND COLD FRONT WILL REACH THE NW GULF WATERS FRI AND EXTEND FROM FROM CENTRAL FLORIDA TO SOUTHERN TEXAS SAT. STRONGER HIGH PRESSURE WILL THEN BUILD FROM NW TO SE ACROSS THE GULF FRI AND SAT. CARIBBEAN SEA... THE UPPER RIDGE OVER THE S GULF OF MEXICO EXTENDS OVER THE NW CARIBBEAN N OF 17N W OF 80W PROVIDING A DIFFLUENT ENVIRONMENT TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 17N W OF 77W TO OVER CUBA AND THROUGH THE YUCATAN CHANNEL. A SMALL UPPER LOW IS OFF THE COAST OF NE NICARAGUA NEAR 14N82W. THE MONSOON TROUGH THAT EXTENDS FROM COLOMBIA NEAR 11N74W ACROSS THE SW CARIBBEAN AND COSTA RICA NEAR 11N84W INTO THE E PACIFIC REGION GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS S OF 13N W OF 70W TO OVER CENTRAL AMERICA. THE UPPER RIDGE ASSOCIATE WITH THE REMNANT LOW OF OPHELIA EXTENDS ACROSS THE LESSER ANTILLES TO OVER THE E CARIBBEAN GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS TO THE ISLANDS FROM SAINT LUCIA TO ANGUILLA. THIS IS LEAVING THE REMAINDER OF THE E CARIBBEAN UNDER CLEAR SKIES TONIGHT. THE REMNANTS OF OPHELIA WILL MOVE NE OF THE LEEWARD/VIRGIN ISLANDS THROUGH WED BEFORE TURNING MORE NORTHERLY. ATLANTIC OCEAN... A NARROW UPPER RIDGE EXTENDS FROM THE N COAST OF CUBA NEAR 23N80W TO BEYOND 32N78W PROVIDING A DIFFLUENT ENVIRONMENT ALOFT AND IS GENERATING SCATTERED/HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS N OF 28N W OF 78W TO INLAND OVER NE FLORIDA AND TO THE COAST OF GEORGIA AND SOUTH CAROLINA. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE W OF A LINE FROM THE E TIP OF CUBA ACROSS ANDROS ISLAND TO 28N79W. AN ELONGATED UPPER TROUGH EXTENDS THROUGH 32N71W ALONG 25N71W TO OVER THE MONA PASSAGE PRODUCING SCATTERED/HEAVY SHOWERS WITH EMBEDDED THUNDERSTORMS FROM 20N-23N BETWEEN 66W-70W AND SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE REMAINDER OF THE AREA FROM 20N-27N BETWEEN 65W-73W. BROAD UPPER RIDGE DOMINATES THE REMAINDER OF THE W ATLC INTO THE CENTRAL ATLC ANCHORED NEAR 31N55W AND PROVIDING DRY STABLE AIR OVER THE AREA N OF 23N BETWEEN 50W-65W. A SURFACE RIDGE DOMINATES THE W AND CENTRAL ATLC N OF 24N BETWEEN 55W-80W ANCHORED BY 1020 MB HIGH JUST W OF BERMUDA. AN UPPER TROUGH EXTENDS S OVER THE E ATLC TO 18N BETWEEN 25W-50W SUPPORTING A COLD FRONT THAT ENTERS THE REGION NEAR 32N32W ALONG 27N36W TO 23N42W AND GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS E OF THE FRONT WITHIN 75 NM OF LINE FROM 27N33W TO BEYOND 32N28W. A WEAK SURFACE RIDGE COVERS THE REMAINDER OF THE E ATLC ANCHORED BY A 1024 MB HIGH ABOUT 200 NM ENE OF THE MADEIRA ISLANDS. THE REMNANTS OF OPHELIA WILL MOVE NE OF THE LEEWARD/VIRGIN ISLANDS THROUGH WED BEFORE TURNING MORE NORTHERLY CONTINUING N THROUGH THE CENTRAL ATLC. THE SURFACE RIDGE WILL REMAIN STATIONARY BUT GRADUALLY WEAKEN THROUGH THU. A WEAK FRONT WILL MOVE INTO THE FAR NW ATLC FRI. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW