000 AXNT20 KNHC 150534 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU SEP 15 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 0515 UTC. ...SPECIAL FEATURES... TROPICAL STORM MARIA IS CENTERED NEAR 28.7N 68.4W AT 15/0600 UTC OR ABOUT 280 NM SW OF BERMUDA MOVING N-NE AT 16 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 999 MB. MAXIMUM SUSTAINED WIND SPEED IS 55 KT WITH GUSTS TO 65 KT. PLEASE SEE THE LATEST FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 90 NM FROM THE CENTER IN THE NE QUADRANT WITH SCATTERED MODERATE/ISOLATED STRONG CONVECTION COVERING THE REMAINDER OF THE AREA FROM 26N-30N BETWEEN 64W-70W AND FROM 23N-36N BETWEEN 66W-59W. MARIA IS EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS OF 1 TO 3 INCHES CAN BE EXPECTED ACROSS BERMUDA THROUGH TODAY. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA ENTERING THE E TROPICAL ATLC NEAR 18N16W THEN S THROUGH A 1012 MB LOW S OF THE CAPE VERDE ISLANDS NEAR 12N22W ALONG 11N31W TO 8N42W. THE ITCZ AXIS CONTINUES FROM 7N45W ALONG 7N49W TO INLAND OVER GUYANA SOUTH AMERICA NEAR 8N59W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE WITHIN 120/150 NM OF LINE FROM 11N16W TO 7N20W AND WITHIN 75/90 NM OF 6N BETWEEN 20W-37W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 60/75 NM OF 12N BETWEEN 21W-34W AND WITHIN 60 NM OF 11N BETWEEN 50W-61W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE ANCHORED OVER S/CENTRAL MEXICO EXTENDS E OVER THE GULF TO 88W WHILE A BROAD UPPER TROUGH COVERS THE REMAINDER OF THE GULF. ESTABLISHED DRY STABLE AIR REMAINS ACROSS THE AREA GIVING THE GULF REMARKABLY CLEAR SKIES AGAIN TONIGHT. THE ONLY EXCEPTION ARE SOME ISOLATED SHOWERS OVER THE FLORIDA KEYS. A WEAK SURFACE RIDGE REMAINS ANCHORED OVER THE N GULF BY A 1016 MB HIGH NEAR 28N90W. SURFACE RIDGE WILL DISSIPATE LATER TODAY. A WEAK COLD FRONT WILL MOVE INTO THE N GULF EARLY THU NIGHT AND MOVE INTO THE W ATLC SAT. CARIBBEAN SEA... THE UPPER TROUGH OVER THE E GULF OF MEXICO EXTENDS S TO OVER THE NW CARIBBEAN N OF 15N W OF 75W GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS WITHIN 75 NM ALONG THE S COAST OF CUBA BETWEEN 75W-83W. AN UPPER RIDGE COVERS THE CENTRAL CARIBBEAN N OF 12N BETWEEN 64W-75W. A SURFACE TROUGH IS BENEATH THIS UPPER FLOW EXTENDING FROM THE S COAST OF THE DOMINICAN REPUBLIC NEAR 18N71W TO 14N72W. THE MONSOON TROUGH EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA NEAR 11N75W ACROSS PANAMA INTO THE E PACIFIC REGION NEAR 9N80W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE SW CARIBBEAN S OF A LINE FROM 12N73W TO COAST RICA NEAR 10N82W. ISOLATED SHOWERS/THUNDERSTORMS DOT THE CENTRAL CARIBBEAN BETWEEN 75W-82W. THE SURFACE TROUGH WILL MOVE W-NW INTO THE CENTRAL CARIBBEAN BY THU NIGHT. ATLANTIC OCEAN... TROPICAL STORM MARIA CONTINUES TO MOVE THROUGH THE W ATLC...SEE SPECIAL FEATURES SECTION ABOVE. THE UPPER TROUGH OVER THE GULF OF MEXICO EXTENDS OVER THE W ATLC W OF 72W WITH ESTABLISHED DRY STABLE AIR OVER THE AREA GIVING THE W ATLC W OF 73W REMARKABLY CLEAR SKIES AGAIN TONIGHT. THE ONLY EXCEPTION IS SOME ISOLATED SHOWERS WITHIN 45 NM OF SE FLORIDA S OF MIAMI AND THE UPPER FLORIDA KEYS. A CUT OFF UPPER LOW IS TO THE SE OF MARIA CENTERED NEAR 21N51W COVERING THE AREA FROM 13N-30N BETWEEN 40W-62W INCLUDING THE LEEWARD ISLANDS AND GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS FROM 20N-25N BETWEEN 48W-53W. A BROAD SURFACE RIDGE DOMINATES THE ATLC N OF 15N E OF 63W WITH A 1026 MB HIGH N OF THE DISCUSSION AREA NEAR 35N51W. TROPICAL STORM MARIA WILL MOVE N OF THE DISCUSSION AREA LATER TODAY AND STRENGTHEN INTO A HURRICANE. A TRAILING SURFACE TROUGH WILL EXTEND FROM S OF MARIA TO THE SE BAHAMAS BY THU AFTERNOON THEN WILL THEN SLOWLY MOVE WNW TO 31N75W TO 21N80W BY LATE MON AS STRONG HIGH PRESSURE BUILDS S ALONG THE U.S. E COAST.A FRONT WILL MOVE INTO THE FAR NW ATLC OF SAT THEN DISSIPATE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW