000 AXNT20 KNHC 031150 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED NOV 03 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION TOMAS IS CENTERED NEAR 13.7N 75.8W AT 03/1200 UTC OR ABOUT 335 NM SSW OF PORT-AU-PRINCE HAITI AND ABOUT 270 NM SSE OF KINGSTON JAMAICA MOVING WNW AT 04 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS RATHER DISORGANIZED IN THE VICINITY OF TOMAS AND LOCATES OVER AN AREA COVERING MUCH OF THE SOUTH-CENTRAL AND SW CARIBBEAN SEA FROM 09N-17N BETWEEN 68W-83W. WHILE THIS AREA REPRESENTS PERIPHERAL CONVECTION...A BURST OF ISOLATED STRONG CONVECTION IS WITHIN 150 NM OF THE CENTER IN THE NW QUADRANT. GIVEN FAVORABLE ATMOSPHERIC AND OCEANIC PARAMETERS IN THE PATH OF THE SYSTEM OVER THE NEXT 72 HOURS...GRADUAL STRENGTHENING IS FORECAST. HOWEVER...BEYOND 72 HOURS...AN UPPER LEVEL TROUGH CURRENTLY OVER THE GULF OF MEXICO WILL PROGRESS EASTWARD AND STEER TOMAS NORTH-NORTHEASTWARD TOWARDS THE WINDWARD PASSAGE AND PORTIONS OF HISPANIOLA. THIS TROPICAL CYCLONE WILL POSE A SIGNIFICANT THREAT OF HEAVY RAINFALL OVER HAITI AND THE DOMINICAN REPUBLIC LATER IN THE WEEK. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/ WTNT31 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. ...ITCZ... ITCZ AXIS IS ALONG 12N17W 09N23W 05N26W 06N43W 08N48W 08N56W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 180 NM S OF THE AXIS BETWEEN 15W-23W. A SURFACE TROUGH IS ANALYZED FROM 03N-10N ALONG 25W WITH SCATTERED MODERATE AND ISOLATED STRONG CONVECTION FROM 03N-09N BETWEEN 23W-29W. ANOTHER SURFACE TROUGH IS ANALYZED FROM 08N45W TO 19N46W WITH ISOLATED MODERATE CONVECTION FROM 09N-17N BETWEEN 40W-46W. A THIRD SURFACE TROUGH IS LOCATED FROM 06N57W TO 15N58W WITH SCATTERED MODERATE AND ISOLATED STRONG CONVECTION FROM 07N-12N BETWEEN 55W-58W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL LOW IS CENTERED OVER SE TEXAS AND EXTENDS AN UPPER LEVEL TROUGH AXIS ALONG THE TEXAS GULF COAST TO CENTRAL MEXICO. THIS SUPPORTS A 1010 MB SURFACE LOW CENTERED OVER NORTHERN LOUISIANA WITH A COLD FRONT EXTENDING SOUTHWARD FROM THE LOW INTO THE GULF NEAR MORGAN CITY ALONG 25N92W TO THE MEXICO COAST NEAR 20N97W. SCATTERED SHOWERS AND TSTMS ARE OCCURRING WITHIN 90 NM EAST OF THE COLD FRONT N OF 26N AND FROM 21N-24N. A STATIONARY FRONTAL BOUNDARY ALSO EXTENDS FROM THE LOW EASTWARD ALONG THE GULF COAST AND NORTHERN FLORIDA INTO THE W ATLC. ISOLATED SHOWERS ARE OCCURRING OVER THE NE GULF N OF 27N BETWEEN 83W AND THE COLD FRONT. WHILE SE TO S WINDS ARE OCCURRING EAST OF THE FRONT...STRONG NW TO N WINDS ARE W OF THE FRONT AND THIS WIND FIELD IS FORECAST TO SPREAD OVER MUCH OF THE GULF W OF 90W BY LATE THURSDAY...WITH GALE CONDITIONS EXPECTED W OF 94W THURSDAY. CARIBBEAN SEA... A LARGE AND VERY BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER THE EASTERN CARIBBEAN NEAR 13N68W. EMBEDDED BENEATH THIS FEATURE ALOFT IS TROPICAL DEPRESSION TOMAS WHICH CONTINUES TO IMPACT THE SOUTH-CENTRAL CARIBBEAN. INFRARED SATELLITE IMAGERY INDICATES SCATTERED SHOWERS AND TSTMS ASSOCIATED WITH THE TROPICAL CYCLONE ARE LOCATED FROM 09N-17N BETWEEN 68W-83W. THE REMAINDER OF THE CARIBBEAN TO THE EAST AND WEST OF TOMAS IS EXPERIENCING SCATTERED SHOWERS AND ISOLATED TSTMS DUE TO LOW-LEVEL CONVERGENCE OF EASTERLY TRADES AND MIDDLE TO UPPER LEVEL DIFFLUENCE WITHIN THE ENVELOPE OF THE UPPER LEVEL ANTICYCLONE. WITH THE TRACK OF TOMAS EXPECTED TO BEGIN A MORE NORTHWARD TRACK TOWARDS THE WINDWARD PASSAGE AND HISPANIOLA BY LATE WEDNESDAY...THE THREAT OF HEAVY RAINFALL WILL REMAIN OVER THE CENTRAL CARIBBEAN THROUGH EARLY NEXT WEEK. ATLANTIC OCEAN... AN UPPER LEVEL RIDGE ACCOMPANIED BY RELATIVELY DRY AIR ALOFT IS OVER THE SOUTHERN FLORIDA PENINSULA AND W ATLC THAT IS PROVIDING OVERALL STABLE CONDITIONS...HOWEVER...LINGERING POCKETS OF LOW- LEVEL MOISTURE FROM A REMNANT FRONTAL BOUNDARY IS GENERATING ISOLATED SHOWERS WITHIN 120 NM OF A LINE FROM 26N68W TO 29N78W. LOW-LEVEL MOISTURE IS ALSO ADVECTING NE FROM THE CARIBBEAN SEA OVER THE STRAITS OF FLORIDA AND EXTREME SOUTHERN FLORIDA WHERE MOSAIC DOPPLER RADAR IS DEPICTING ISOLATED SHOWERS FROM 23N-26N BETWEEN 78W-82W. ALONG THE SOUTHEASTERN PERIPHERY OF THE W ATLC SURFACE RIDGE...A SHEARLINE IS ANALYZED FROM 26N52W TO 22N63W WITH ISOLATED SHOWERS OCCURRING WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. FARTHER EAST OVER THE CENTRAL ATLC...A WEAKNESS WITHIN THE SUBTROPICAL RIDGE BETWEEN 43W AND 50W IS WHERE A SURFACE TROUGH IS FOUND FROM 22N49W TO BEYOND 32N45W. ISOLATED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE SURFACE TROUGH AND FROM 22N-28N BETWEEN 43W-47W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1026 MB HIGH CENTERED NE OF THE AZORES NEAR 40N19W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN