000 AXNT20 KNHC 311803 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE AUG 31 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...SPECIAL FEATURES... THE CENTER OF HURRICANE EARL AT 31/1800 UTC WAS ESTIMATED NEAR 21.5N 68.5W...OR ABOUT 170 NM TO THE E OF GRAND TURK ISLAND...MOVING WEST-NORTHWESTWARD 12 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 940 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 116 KT WITH GUSTS TO 140 KT. PLEASE READ THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC AND THE LATEST PUBLIC ADVISORY UNDER MIATCPAT2/WTNT32 KNHC FOR MORE DETAILS. NUMEROUS STRONG SHOWERS AND THUNDERSTORMS ARE FROM 18N TO 25N BETWEEN 65W AND 71W. THE CENTER OF TROPICAL STORM FIONA AT 31/1500 UTC IS NEAR 16.3N 56.8W...MOVING WEST-NORTHWESTWARD 21 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 35 KT WITH GUSTS TO 45 KT. PLEASE READ THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC AND THE PUBLIC ADVISORY UNDER MIATCPAT3/WTNT33 KNHC FOR MORE DETAILS. STRONG RAINSHOWERS AND THUNDERSTORMS ARE FROM 13N TO 20N BETWEEN 54W AND 60W. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 16N27W 11N29W 5N29W. A 1009 MB LOW PRESSURE CENTER IS EMBEDDED IN THE WAVE NEAR 10N28W. THE WAVE IS MOVING WESTWARD 10-15 KT. SCATTERED STRONG RAINSHOWERS AND THUNDERSTORMS ARE FROM 6N TO 13N BETWEEN 29W AND 36W. THERE IS A LOW CHANCE OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...THE ITCZ... ITCZ AXIS IS ANALYZED FROM WEST AFRICA OVER GUINEA-BISSAU NEAR 12N15W TO 9N21W...RESUMING WEST OF A TROPICAL WAVE NEAR 8N34W CONTINUING NW ALONG 9N41W TO 12N47W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS OVER THE COASTAL WATERS OF WEST AFRICA E OF 20W FROM 7N TO 17N. ...DISCUSSION... THE GULF OF MEXICO... WATER VAPOR IMAGERY SHOWS ANTI-CYCLONIC FLOW ALOFT OVER SE TEXAS AND AN UPPER LEVEL LOW OVER EAST CENTRAL MISSISSIPPI. THE UPPER LEVEL FLOW BETWEEN THESE TWO FEATURES IS GENERATING DIFFLUENCE FLOW ALOFT OVER THE CENTRAL AND NORTH CENTRAL GULF...PUSHING A RATHER WEAK UPPER LEVEL LONGWAVE SOUTH INTO THE GULF...WITH AXIS EXTENDING FROM THE FLORIDA PANHANDLE NEAR PANAMA CITY TO MEXICO NEAR TAMPICO. THIS SCENARIO IS SUPPORTING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS MUCH OF THE BASIN...ESPECIALLY E OF 90W...WITH THE MOST CONVECTIVE AREA FROM 22N TO 30N BETWEEN 82W AND 90W. THIS AREA OF CONVECTION IS EXPECTED TO SHIFT SW OVER THE NEXT 24 TO 36 HOURS AFFECTING THE COASTAL WATERS SURROUNDING THE YUCATAN PENINSULA N OF 20N. A NEARLY STATIONARY SURFACE TROUGH IS OVER THE WESTERN BAY OF CAMPECHE ALONG 95W S OF 23N ENHANCING SCATTERED HEAVY SHOWERS AND ISOLATED THUNDERSTORMS W OF 93W S OF 23N. COMPUTER MODELS SUGGEST THIS AREA OF CONVECTION WILL LINGER OVER THE NEXT 24 TO 48 HOURS. THE CARIBBEAN SEA... THE EASTERN CARIBBEAN N OF 16N BETWEEN 64W AND 69W CONTINUES TO BE THE MAIN AREA OF CONCERN AS HURRICANE EARL EXTENDS MULTIPLE BANDS OF HEAVY SHOWERS AND THUNDERSTORMS TO THE AREA FOCUSED OVER THE MONA PASSAGE...PUERTO RICO...AND THE US/UK VIRGIN ISLANDS. THIS AREA OF CONVECTION WILL SLOWLY MOVE NNW OUT THE AREA OVER THE NEXT 24 HOURS. HOWEVER...SCATTERED SHOWERS WILL REMAIN OVER THE BOXED AREA THROUGH THURSDAY. THE FAR SW BASIN S OF 11N W OF 76W...DUE TO CLOSE PROXIMITY TO THE ITCZ EXTENDING ACROSS PANAMA TO NORTHERN COLOMBIA. DRY AIR ALOFT IS SEEN ELSEWHERE ACROSS THE CARIBBEAN NOTED ON WATER VAPOR IMAGERY. THIS UPPER LEVEL AIRMASS IS SUPPRESSING CONVECTION ACROSS THE CENTRAL AND WESTERN CARIBBEAN...WITH A FEW ISOLATED SHOWERS DEVELOPING OVER THE FAR NW BASIN W OF 82W N OF 19N...EXPECTED TO BECOME MORE PROMINENT OVER THE NEXT 24 HOURS...ESPECIALLY ACROSS THE YUCATAN CHANNEL. THE ATLANTIC OCEAN... STRONG SUBSIDENCE ALOFT IS NOTED ON WATER VAPOR IMAGERY W OF 71W ASSOCIATED TO AN UPPER LEVEL TROUGH DELVING SOUTHWARD ACROSS THE WESTERN ATLC. THIS FEATURE IS PROVIDING MOSTLY FAIR WEATHER CONDITIONS TO THE WESTERN ATLC. HOWEVER...HURRICANE EARL IS TO THE SE OF THIS AREA OF SUBSIDENCE AND IS APPROACHING THIS REGION WITH CONVECTION...SEE SPECIAL FEATURES FOR MORE DETAILS. SURFACE ANTICYCLONIC FLOW IS ELSEWHERE ACROSS THE ATLC...AROUND A 1021 MB HIGH CENTERED NEAR 29N43W. DRY SAHARAN AIR ALOFT IS ALSO NOTED ON SATELLITE VISIBLE E OF 50W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA