000 AXNT20 KNHC 131141 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE SEP 13 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...SPECIAL FEATURES... TROPICAL STORM MARIA IS CENTERED NEAR 21.9N 67.9W AT 13/1200 UTC OR ABOUT 280 NM E OF THE SOUTHEASTERN BAHAMAS AND ABOUT 645 NM S-SW OF BERMUDA MOVING N-NW AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 45 KT WITH GUSTS TO 55 KT. PLEASE SEE THE LATEST FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. MARIA CONTINUES TO BE IN SHEAR ENVIRONMENT WITH SCATTERED MODERATE/ STRONG CONVECTION COVERING THE AREA FROM 17N-21N BETWEEN 64W-68W INCLUDING THE VIRGIN ISLANDS AND PUERTO RICO. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 20N-23N BETWEEN 62W-65W. MARIA IS EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS OF 2-4 INCHES WITH ISOLATED MAXIMUM AMOUNTS OF 8 INCHES OVER THE THE VIRGIN ISLANDS...PUERTO RICO...AND PORTIONS OF THE NORTHERN LEEWARD ISLANDS THROUGH THIS EVENING. ...TROPICAL WAVES... TROPICAL WAVE IS IN THE W TROPICAL ATLC EXTENDING FROM 20N56W TO 10N58W MOVING W 15-20 KT. WAVE IS EMBEDDED WITHIN DEEP LAYER MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. WAVE IS WELL DEFINED IN THE UPPER LEVEL SATELLITE WINDS. WAVE IS BENEATH THE OUTFLOW FROM TROPICAL STORM MARIA TO THE NW ENHANCING CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION WITHIN 90/120 NM OF LINE FROM 11N61W TO 22N54W. TROPICAL WAVE IS IN THE NW CARIBBEAN ALONG 87W S OF 20N MOVING W NEAR 5 KT. WAVE WAS REPOSITIONED SLIGHTLY TO THE E BASED A LATE EVENING ASCAT PASS AND SATELLITE SIGNATURE. ABUNDANCE OF TROPICAL MOISTURE COVERS THE ENTIRE CARIBBEAN AND S GULF OF MEXICO INCLUDING THE YUCATAN PENINSULA AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ARE S OF 19N W OF 83W TO INLAND OVER CENTRAL AMERICA AND THE YUCATAN PENINSULA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA ENTERING THE E TROPICAL ATLC NEAR 17N16W ALONG 12N19W 9N28W 8N39W TO 6N44W. THE 1013 MB LOW THAT WAS NEAR 9N38W IS NO LONGER DISCERNIBLE. THERE CONTINUES TO BE NO CONVERGING NE/SE FLOW...SO NO ITCZ AXIS. SCATTERED MODERATE/STRONG CONVECTION IS FROM 10N-15N E OF 20W TO THE COAST OF W AFRICA INCLUDING GUINEA-BISSAU...GAMBIA...AND SENEGAL. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 90 NM ALONG THE COAST OF W AFRICA BETWEEN LIBERIA AND GUINEA. SCATTERED MODERATE CONVECTION IS FROM 5N-8N BETWEEN 30W-34W WITH CLUSTERS OF SIMILAR CONVECTION FROM 5N-10N BETWEEN 45W-60W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER TROUGH COVERS THE FAR E CONUS INTO THE GULF N OF 22N USHERING IN DRY STABLE AIR OVER THE GULF GIVING THE AREA N OF 24N REMARKABLY CLEAR SKIES THIS MORNING. AN UPPER RIDGE ANCHORED IN THE NW CARIBBEAN EXTENDS OVER THE FAR S GULF. DIFFLUENT FLOW BETWEEN THE UPPER RIDGE IN THE CARIBBEAN AND THE UPPER TROUGH OVER THE GULF IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS IN THE BAY OF CAMPECHE S OF 20N E OF 96W AND ISOLATED SHOWERS ACROSS THE REMAINDER OF THE S GULF S OF 24N INCLUDING THE FLORIDA KEYS AND THE STRAITS OF FLORIDA. A WEAK SURFACE RIDGE COVERS MUCH OF THE GULF AND AT 13/0900 UTC IS ANCHORED BY A 1018 MB HIGH NEAR 28N89W. SURFACE RIDGE WILL REMAIN NEARLY STATIONARY OVER THE N GULF THROUGH FRI. THE TROPICAL WAVE IN THE NW CARIBBEAN WILL MOVE SLOWLY OVER THE YUCATAN PENINSULA TODAY THROUGH WED THEN ACROSS THE BAY OF CAMPECHE THU AND FRI. CARIBBEAN SEA... TROPICAL STORM MARIA CONTINUES TO PRODUCE CONVECTION OVER THE FAR NE CARIBBEAN...SEE SPECIAL FEATURES SECTION ABOVE. AN UPPER RIDGE COVERS THE NW CARIBBEAN ANCHORED ALONG THE COAST OF THE YUCATAN NEAR 18N88W ENHANCING THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVE. EASTERLY FLOW ALOFT DOMINATES THE REMAINDER OF THE CARIBBEAN. THE MONSOON TROUGH EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA NEAR 9N75W ACROSS PANAMA ALONG 9N81W INTO THE E PACIFIC REGION ALONG THE COSTA RICA/NICARAGUA BORDER GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 11N TO INLAND OVER COLOMBIA AND PANAMA BETWEEN 75W-78W. SCATTERED SHOWERS ARE MOVING OVER THE LESSER ANTILLES AHEAD OF THE TROPICAL WAVE APPROACHING THE ISLANDS FROM THE W TROPICAL ATLC. TROPICAL WAVE ALONG THE YUCATAN COAST WILL SLOWLY MOVE ACROSS THE YUCATAN PENINSULA THROUGH WED. THE TROPICAL ATLC TROPICAL WAVE WILL REACH THE LEEWARD ISLANDS TONIGHT CROSSING INTO THE E CARIBBEAN THROUGH WED REACHING THE CENTRAL CARIBBEAN THU AND BE OVER THE W CARIBBEAN FRI AND SAT. ATLANTIC OCEAN... THE UPPER TROUGH OVER THE FAR E CONUS EXTENDS OVER THE W ATLC N OF 23N W OF 74W WITH A SHORTWAVE UPPER TROUGH EXTENDING FROM 31N77W TO THE FLORIDA COAST NEAR WEST PALM BEACH SUPPORTING A SURFACE TROUGH THAT AT 13/0900 UTC EXTENDS FROM 32N77W ALONG 27N80W TO 25N80W GENERATING SHOWERS/THUNDERSTORMS WITHIN 60 NM OF LINE FROM 27N80W TO 32N74W AND SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 90 NM OF LINE FROM 25N80W ACROSS THE N BAHAMA ISLANDS TO BEYOND 32N73W. AN UPPER LOW IS BEGINNING TO PULL N AWAY FROM TROPICAL STORM MARIA AND IS NOW CENTERED NEAR 29N65W. AN UPPER TROUGH AXIS EXTENDS INTO THE CENTRAL ATLC THROUGH 32N37W TO AN UPPER LOW NEAR 26N40W GENERATING ISOLATED SHOWERS FROM 23N-26N BETWEEN 41W-44W. A BROAD SURFACE RIDGE DOMINATES THE ATLC N OF 18N E OF 50W AND N OF 26N BETWEEN 50W-80W WITH A 1023 MB HIGH IN THE CENTRAL ATLC NEAR 32N56W. TROPICAL STORM MARIA WILL MOVE NW THROUGH TODAY THEN TURN MORE NORTHERLY AND BE N OF THE DISCUSSION AREA LATE WED. A TROUGH WILL LINGER OVER THE W ATLC THU AND FRI MOVING W ON SAT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW