000 AXNT20 KNHC 071736 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST SUN NOV 07 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 1715 UTC. ...SPECIAL FEATURE... HURRICANE TOMAS WAS DOWNGRADED TO TROPICAL STORM AT 07/1500 UTC. TROPICAL STORM TOMAS IS CENTERED NEAR 26.0N 69.6W AT 07/1500 UTC MOVING N AT 5 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 997 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. TOMAS IS RAPIDLY WEAKENING...THUS THERE IS NO ASSOCIATED DEEP CONVECTION REMAINING. A STATIONARY FRONT REMAINS JUST NW OF TOMAS PRODUCING SHOWERS OVER AND N OF TOMAS. ...THE ITCZ... THE ITCZ AXIS IS FROM 7N11W 4N25W 3N37W 5N49W 4N52W. THE ITCZ IS FAIRLY QUIET THIS AFTERNOON WITH CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION WITHIN 150/180 NM ALONG THE COAST OF SW AFRICA S OF 8N E OF 2W. ...DISCUSSION... GULF OF MEXICO... HIGH PRESSURE REMAINS IN CONTROL OF THE GULF THIS AFTERNOON ANCHORED BY A PAIR OF 1034 MB HIGHS OVER THE N APPALACHIAN MOUNTAINS AND A WEAKER 1028 MB HIGH OVER SE MEXICO NEAR 21N98W. THE STRONG UPPER TROUGH REMAINS OVER THE GULF WATERS IN WAKE OF OF THE RECENT FRONTAL PASSAGE GIVING THE GULF COOL NORTHERLY WINDS AND COLD AIR STRATOCUMULUS CLOUDS OVER MOST OF THE GULF. STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT REIGNS LIMITING ANY SHOWER ACTIVITY. EXPECT SURFACE COLD AIR ADVECTION WITH NO CHANGE IN WINDS TO CONTINUED ACROSS THE AREA FOR THE NEXT 24 HOURS. CARIBBEAN SEA... BROAD UPPER RIDGE COVERS THE CARIBBEAN ANCHORED S OF HISPANIOLA NEAR 16N72W DRAWING MOIST AIR ALOFT FROM TROPICAL STORM TOMA S OVER THE E CARIBBEAN. STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT REMAINS OVER THE W CARIBBEAN. A SURFACE TROUGH EXTENDS FROM S OF TOMAS THROUGH THE MONA PASSAGE TO 16N68W WITH THE REMNANTS CONTINUING TO OVER THE GULF OF VENEZUELA. SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE N OF 15N BETWEEN 63W-73W AND WITHIN 75/90 NM OF LINE FROM 15N70W TO OVER THE GULF OF VENEZUELA. A TIGHT PRESSURE GRADIENT IS TO THE W OF THIS BOUNDARY PRODUCING MODERATE TO FRESH NORTHERLY WINDS AND ADVECTING COLD AIR STRATOCUMULUS CLOUDS S FROM THE GULF OF MEXICO AND THE W ATLC. LOW LEVEL AND UPPER LEVEL CONVERGENCE IS GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS OVER THE SW CARIBBEAN S OF 12N TO OVER PANAMA BETWEEN 78W-82W. EXPECT THE SURFACE TROUGH TO MEANDER OVER THE CENTRAL CARIBBEAN OVER THE NEXT FEW DAYS AS A COLD FRONT WILL MOVE E OVER THE NE CARIBBEAN TONIGHT THROUGH TUE STALLING ON WED. ATLANTIC OCEAN... TROPICAL STORM TOMAS REMAINS OVER THE W ATLC...SEE SPECIAL FEATURES ABOVE. THE UPPER TROUGH OVER THE GULF OF MEXICO EXTENDS OVER THE W ATLC N OF 27N W OF 70W SUPPORTING A STATIONARY FRONT ENTERING THE REGION NEAR 32N68W TO N OF TOMAS NEAR 28N70W. SCATTERED SHOWERS ARE N OF 25N BETWEEN 66W-72W. A SURFACE TROUGH EXTENDS FROM SE OF TOMAS NEAR 24N68W THROUGH THE MONA PASSAGE INTO THE CARIBBEAN WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 120 NM E OF THE SURFACE TROUGH. A SHARP HIGH AMPLITUDE UPPER TROUGH IS OVER THE CENTRAL ATLC EXTENDING THROUGH 32N53W S TO 12N53W SUPPORTING A SURFACE TROUGH EXTENDING FROM 33N50W ALONG 29N53W TO 24N53W. BROAD UPPER RIDGE TO THE E IS PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 18N-30N BETWEEN 38W-50W. THE E ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1041 MB HIGH WELL N OF THE AZORES. EXPECT TOMAS TO CONTINUE TO WEAKEN BECOMING A POST TROPICAL LOW OVER THE NEXT 24 HOURS THEN DEVELOPING A FRONTAL BOUNDARY THAT WILL MOVE SE TO OVER THE NE CARIBBEAN THEN CONTINUE EASTWARD. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW