000 AXNT20 KNHC 022348 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED OCT 02 2013 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... TROPICAL STORM JERRY IS CENTERED NEAR 29.3N 42.6W AT 02/2100 UTC OR ABOUT 940 NM W-SW OF THE AZORES MOVING NE AT 6 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1009 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. SEE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 27N- 31N BETWEEN 40W-45W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 45 NM OF LINE FROM 25N43W TO 27N41W. THE AREA OF INTEREST IN THE W CARIBBEAN IS ANALYZED AS A SURFACE TROUGH THAT EXTENDS FROM THE SE GULF OF MEXICO NEAR 26N86W THROUGH WEAK 1007 MB LOW IN THE W CARIBBEAN NEAR 19N86W TO THE COAST OF HONDURAS NEAR 15N85W. AN AIR FORCE RESERVE UNIT HURRICANE HUNTER AIRCRAFT HAS EXTENSIVELY INVESTIGATED THIS BROAD AREA OF LOW PRESSURE AND DETERMINED THAT THE SYSTEM DID NOT HAVE A WELL-DEFINED CIRCULATION. HOWEVER...THIS SYSTEM IS PRODUCING WINDS TO GALE FORCE AND HAS THE POTENTIAL TO BECOME A TROPICAL STORM AT ANY TIME TONIGHT OR ON THURSDAY. THE LOW IS EXPECTED TO MOVE N-NW INTO THE S GULF OF MEXICO BY EARLY THU. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. REGARDLESS OF DEVELOPMENT THIS SYSTEM COULD PRODUCE LOCALLY HEAVY RAINS COULD AFFECT THE CAYMAN ISLANDS...PORTIONS OF CUBA...AND PORTIONS OF THE YUCATAN PENINSULA DURING THE NEXT DAY OR TWO. HEAVY SHOWERS WITH EMBEDDED ISOLATED THUNDERSTORMS ARE FROM 19N-22N BETWEEN 83W-87W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOTTING THE REMAINDER OF W CARIBBEAN AND SE GULF OF MEXICO FROM 16N-27N BETWEEN 80W-89W INCLUDING PORTIONS OF THE YUCATAN PENINSULA...W CUBA...THE CAYMAN ISLANDS...AND S FLORIDA. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 17N35W TO 11N35W MOVING W AT 10-15 KT. WAVE IS EMBEDDED WITHIN A BROAD AREA OF OF RELATIVELY DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER...LITTLE OR NO CURVATURE INDICATED IN THE SATELLITE WINDS. NO ASSOCIATED CONVECTION. TROPICAL WAVE EXTENDS FROM 21N49W TO 11N51W MOVING W NEAR 20 KT. TOTAL PRECIPITABLE WATER IMAGERY INDICATES DRY AIR HAS INTRUDED INTO THE WAVE LEAVING THE ONLY THE S PORTION WITH DEEP MOISTURE. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 180 NM W OF THE WAVE FROM 11N-13N. ...ITCZ/MONSOON TROUGH... MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 13N17W ALONG 9N22W TO 8N27W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 10N40W 22N50W TO 9N57W. SCATTERED MODERATE/ ISOLATED STRONG CONVECTION IS FROM 9N-12N BETWEEN 24W-28W. AN E/W UPPER RIDGE IS ACROSS THE TROPICAL ATLC AND IS PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOTTING THE AREA BETWEEN THE TROPICAL WAVES FROM 11N-22N BETWEEN 36W-45W. ...DISCUSSION... GULF OF MEXICO... A NARROW UPPER TROUGH EXTENDS FROM A SHORTWAVE UPPER TROUGH OVER THE MIDDLE MISSISSIPPI VALLEY INTO THE GULF OF MEXICO OVER THE LOUISIANA/TEXAS BORDER TO THE W BAY OF CAMPECHE NEAR VERACRUZ MEXICO. THE UPPER RIDGE ASSOCIATED WITH THE AREA OF INTEREST IN THE W CARIBBEAN WITH THE AXIS EXTENDING ACROSS CUBA NEAR HAVANA TO OVER THE FLORIDA PENINSULA INCLUDING THE E GULF OF MEXICO. THIS UPPER RIDGE IS PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS N OF 28N TO INLAND OVER THE N GULF COAST BETWEEN PANAMA CITY FLORIDA TO GRAND ISLE LOUISIANA. SEE SPECIAL FEATURES ABOVE FOR THE ACTIVITY OVER THE SE GULF. A WEAK SURFACE RIDGE COVERS THE N GULF ANCHORED BY A 1020 MB HIGH OVER WESTERN NORTH CAROLINA AND WILL SHIFT N THROUGH TONIGHT AHEAD THE LOW CURRENTLY IN THE W CARIBBEAN. THIS LOW WILL MOVE INTO CENTRAL GULF THU THEN SHIFT NE ACROSS NE GULF FRI THROUGH SUN. CARIBBEAN SEA... THE PRIMARY AREA OF INTEREST IS THE SURFACE LOW/TROUGH IN THE W CARIBBEAN. SEE SPECIAL FEATURES ABOVE. AN UPPER RIDGE COVERS THE THE W CARIBBEAN W OF 80W ASSOCIATED WITH THE SYSTEM IN THE SPECIAL FEATURES. THE BROAD E/W UPPER RIDGE OVER THE TROPICAL ATLC COUPLED WITH THE UPPER RIDGE OVER THE W CARIBBEAN ARE INDUCING AN INVERTED UPPER TROUGH OVER THE E CARIBBEAN WITH THE AXIS EXTENDING FROM THE ABC ISLANDS TO OVER THE VIRGIN/LEEWARD ISLANDS. CLUSTERS OF SCATTERED SHOWERS/THUNDERSTORMS ARE N OF 17N BETWEEN 66W-80W INCLUDING PORTIONS OF THE GREATER ANTILLES FROM PUERTO RICO TO E CUBA AND JAMAICA. ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS DOT THE SE CARIBBEAN S OF 16N BETWEEN 59W-64W INCLUDING THE WINDWARD ISLANDS. THE MONSOON TROUGH EXTENDS ALONG 10N BETWEEN COLOMBIA AND COSTA RICA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 45 NM OF LINE FROM 11N80W TO NE NICARAGUA NEAR 14N83W. THE REMAINDER OF THE CENTRAL CARIBBEAN IS UNDER REMARKABLY CLEAR SKIES THIS EVENING. LOW OVER THE W CARIBBEAN WILL MOVE NW ACROSS THE YUCATAN PENINSULA TONIGHT THROUGH THU. FRESH TO STRONG SE WINDS ARE EXPECTED E OF SURFACE TROUGH WITH AN AREA OF GALE FORCE WINDS N OF 20N BETWEEN 80W-86W. GENTLE TO MODERATE E-SE TRADES PREVAIL ACROSS REMAINDER OF BASIN THROUGH MON. HISPANIOLA... CURRENTLY SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER S HAITI AND SW DOMINICAN REPUBLIC DUE TO THE UPPER RIDGE ASSOCIATED WITH THE AREA OF INTEREST IN THE W CARIBBEAN. NORTHERLY WINDS ALOFT AS WELL AS LOW LEVEL MOISTURE WILL CONTINUE ACROSS THE ISLAND THROUGH THE WEEKEND. GIVEN THE PERSISTENCE OF LOW LEVEL MOISTURE...PEAK DAYTIME HEATING...AND INSTABILITY...AFTERNOON SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS COULD GENERATE DAILY. ATLANTIC OCEAN... TROPICAL STORM JERRY IS IN THE E/CENTRAL ATLC. SEE SPECIAL FEATURES ABOVE. THE UPPER RIDGE ASSOCIATED WITH THE AREA OF INTEREST IN THE W CARIBBEAN COVERS THE FAR W ATLC W OF 76W. AN UPPER TROUGH EXTENDS ACROSS BERMUDA THROUGH A WEAK UPPER LOW NEAR 27N69W TO 23N72W SUPPORTING A SURFACE TROUGH THAT EXTENDS THROUGH 32N72W TO 29N79W. THIS UPPER TROUGH IS AMPLIFYING AN UPPER RIDGE THAT EXTENDS S OF THE BASE OF THE UPPER TROUGH ALONG 21N71W 26N62W TO 32N53W AND PROVIDING DIFFLUNCE ALOFT TO GENERATE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 22N-29N BETWEEN 61-69W. A WEAK 1018 MB HIGH IS LOCATED NEAR 28N64W. A SURFACE RIDGE COVERS THE E ATLC ANCHORED BY A 1020 MB HIGH NEAR 26N33W. W ATLC SURFACE RIDGE HAS SHIFTED S SLIGHTLY AHEAD OF THE WEAK SURFACE TROUGH. THIS RIDGE WILL SHIFT N TONIGHT AS THE TROUGH WEAKENS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW