000 AXNT20 KNHC 301747 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT OCT 30 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 TROPICAL STORM TOMAS AT 30/1800 UTC IS NEAR 13.4N 61.0W...MOVING WNW NEAR 10 KT. TOMAS IS ABOUT 10 MI...15 KM NE OF ST. VINCENT...AND ABOUT 25 MI...40 KM S OF ST. LUCIA. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 992 MB. THE MAXIMUM SUSTAINED WIND SPEED IS 65 KT WITH GUSTS TO 80 KT. PLEASE READ THE 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. NUMEROUS STRONG CONVECTION IS FROM 14N-17N BETWEEN 55W-60W. NUMEROUS MODERATE/SCATTERED STRONG CONVECTION COVERS FROM 11N TO 15N BETWEEN 56W AND 63W...INCLUDING MOST OF THE WINDWARD ISLANDS S OF 17N. THESE AREAS SHOULD BE PREPARED FOR GUSTY WINDS AND HEAVY RAINFALL TO CONTINUE WITH THE POTENTIAL THREAT OF FLOODING. THE CENTER OF HURRICANE SHARY AT 30/1500 UTC IS NEAR 35.9N 55.6W...OR ABOUT 580 MI...935 KM ENE OF BERMUDA. SHARY IS MOVING NE AT 35 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 989 MB. THE MAXIMUM SUSTAINED WIND SPEED IS 65 KT WITH GUSTS TO 80 KT. PLEASE READ THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. SHARY REMAINS A SMALL TROPICAL CYCLONE EMBEDDED IN A STRONG COLD FRONT. THE CYCLONE WILL LIKELY WEAKEN TODAY AS IT MOVES INTO EVEN STRONGER SHEAR AND OVER COOLER WATER. ...THE ITCZ... THE ITCZ IS ANALYZED FROM THE SOUTHERN COAST OF LIBERIA NEAR 4N8W WESTWARD TO 8N22W...RESUMING ALONG 9N25W 8N31W 9N38W...RESUMING AGAIN ALONG 8N44W 8N52W. A SURFACE TROUGH IS JUST S OF THE CAPE VERDE ISLANDS FROM 14N23W TO 6N24W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS NEAR THE TROUGH AXIS S OF 11N. A SECOND EMBEDDED SURFACE TROUGH IS ALONG 40W FROM 5N-10N. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 5N-10N BETWEEN 19W-30W. SIMILAR CONVECTION IS FROM 4N-8N BETWEEN 36W-45W. ...DISCUSSION... THE GULF OF MEXICO... A NEARLY STATIONARY BOUNDARY REMAINS ACROSS THE SOUTHEAST GULF...ENTERING THROUGH THE STRAITS OF FLORIDA TO THE NORTHERN COASTAL WATERS OF THE YUCATAN PENINSULA ALONG 24N80W 23N85W 22N89W. THIS FEATURE IS JUST A SECTION OF A LONGER FRONTAL SYSTEM THAT EXTENDS ACROSS THE WESTERN ATLC...SUPPORTED BY A DEEP LAYERED TROUGH THAT MOVES ACROSS THE NW ATLC BASIN. SCATTERED WEAK SHOWERS ARE WITHIN 50 NM ON EITHER SIDE OF THE STATIONARY FRONT. MARINE OBS ACROSS THE GULF INDICATE EASTERLY WINDS OF 10 KT TO 15 KT N OF 24N E OF 95W. A NEARLY STATIONARY SURFACE TROUGH IS OVER THE BAY OF CAMPECHE ANALYZED ALONG 23N91W 21N93W 18N93W...PRODUCING SCATTERED WEAK TO ISOLATED MODERATE CONVECTION S OF 22N W OF 92W. WINDS UP TO 30 KT ARE POSSIBLE TO THE WEST OF THE TROUGH S OF 22N. A VERY DRY AND STABLE AIRMASS ALOFT CONTINUES TO TAKE PLACE ACROSS THE REGION...AS AN UPPER RIDGE OF HIGH PRESSURE WITH ANTI-CYCLONIC FLOW CURRENTLY CENTERED OVER THE FAR NW GULF MOVES OVER THE BASIN SUPPRESSING DEEP CONVECTION FOR AT LEAST THE NEXT 24 HOURS. THE CARIBBEAN SEA... THE MAIN FEATURE OF CONCERN THIS AFTERNOON IS HURRICANE TOMAS AFFECTING THE LESSER ANTILLES WITH STRONG CONVECTION. THE ERN CARIBBEAN SHOULD MONITOR THE PROGRESS OF TOMAS AS IT TRACKS WNW. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS. ELSEWHERE ACROSS THE BASIN...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE LOCATED IN THE SOUTHWESTERN BASIN S OF 13N ASSOCIATED WITH AN EXTENSION OF THE ITCZ. STREAMLINE ANALYSIS FROM MODEL DATA REFLECTS MID TO UPPER LEVEL CONVERGENCE CAUSING SOME SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS FROM 15N-19N BETWEEN 71W-77W. THE ATLANTIC OCEAN... A DEEP LAYER TROUGH IS OVER THE NW ATLC BASIN...SUPPORTING A COLD FRONT THAT ENTERS OUR AREA OF DISCUSSION THROUGH 32N60W AND CONTINUES SW ALONG 29N65W 27N71W 26N75W...BECOMING STATIONARY FROM THIS POINT TO THE STRAITS OF FLORIDA. SCATTERED MODERATE TO HEAVY SHOWERS AND POSSIBLE THUNDERSTORMS ARE WITHIN 30 NM ON EITHER SIDE OF THE COLD FRONT. ISOLATED WEAK SHOWERS ARE WITHIN 20 NM EITHER SIDE OF THE STATIONARY FRONT. HURRICANE SHARY IS NOW EMBEDDED IN THIS FRONTAL SYSTEM AND WILL CONTINUE TO RAPIDLY MOVE NE AND BECOME EXTRA-TROPICAL IN ABOUT 12 HOURS. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS. A REGION OF MID TO UPPER LEVEL CONVERGENCE IS AHEAD OF THE COLD FRONT AND SUPPORTS A SURFACE TROUGH ANALYZED ALONG 30N55W 25N60W 19N67W. SCATTERED WEAK SHOWERS ARE WITHIN 60NM W OF THE TROUGH AXIS N OF 24N. EAST OF THIS AREA OF CONVERGENCE...A WEAK SURFACE TROUGH IS ANALYZED FROM 27N48W TO 21N45W WITH NO ASSOCIATED DEEP CONVECTION. THE REMAINDER OF THE BASIN IS DOMINATED BY SURFACE RIDGING ANCHORED BY A 1027 MB HIGH NEAR 33N35W UNDER A DRY AIR MASS SUPPORTING FAIR WEATHER ACROSS THE AREA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA/MONTALVO