000 AXNT20 KNHC 072358 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED OCT 07 2015 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 JOAQUIN IS CENTERED NEAR 41.5N 41.0W AT 07/2100 UTC OR ABOUT 610 NM...1125 KM ESE OF CAPE RACE NEWFOUNDLAND MOVING E AT 32 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 977 MB. MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH GUSTS TO 75 KT. MULTILAYERED CLOUDS WITH SHOWERS AND ISOLATED CONVECTION WAS NOTED FROM 41N TO 47N BETWEEN 33W AND 41W. THE STORM CONTINUES MOVING OVER COOLER WATERS AND IS BEGINNING ITS TRANSITION TO AN EXTRATROPICAL CYCLONE. SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE HAS BEEN ANALYZED FROM 14N24W TO 06N27W OVER THE EASTERN ATLC MOVING W AT 10 TO 15 KT. A TILTED 700 MB TROUGH IS EVIDENT IN MODEL STREAMLINES WITH A SURGE OF DEEP MOISTURE PRECEDING THE WAVE. ISOLATED MODERATE CONVECTION WAS NOTED NEAR THE INTERSECTION OF THE WAVE AXIS AND THE ITCZ FROM 07N TO 10N BETWEEN 26W AND 30W. A LOW AMPLITUDE TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC EXTENDING FROM 10N50W TO 03N50W...MOVING W AT 15 TO 20 KT OVER THE PAST 24 HOURS. THE WAVE COINCIDES WITH SUBTLE 700 MB TROUGHING BETWEEN 45W AND 55W. SCATTERED MODERATE CONVECTION WAS NOTED WELL AHEAD OF THE WAVE FROM 07N TO 12N BETWEEN 41W AND 48W. A TROPICAL WAVE IS APPROACHING THE LESSER ANTILLES WITH AXIS EXTENDING FROM 20N58W TO 10N60W...MOVING W AT AROUND 15 KT OVER THE PAST 24 HOURS. THE WAVE COINCIDES WITH A FAIRLY SHARP 700 MB TROUGH BETWEEN 58W AND 64W AND REMAINS EMBEDDED WITHIN AN AREA OF MODERATE TO HIGH MOISTURE AND DIFFLUENT FLOW ALOFT. A BROAD AREA OF MULTILAYERED CLOUDS WAS NOTED FROM 15N-26N BETWEEN 50W- 60W. SCATTERED MODERATE CONVECTION WAS FOCUSED FROM 16N-19N BETWEEN 56W AND 60W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM THE AFRICAN COAST NEAR 13N17W TO 10N22W. THE ITCZ AXIS BEGINS W OF A TROPICAL WAVE NEAR 08N28W TO 05N40W TO 07N48W. OTHER THAN CONVECTION ASSOCIATED WITH THE E ATLC TROPICAL WAVE...ISOLATED MODERATE CONVECTION WAS NOTED WITHIN 60 NM OF THE ITCZ AXIS BETWEEN 30W AND 35W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL ANTICYCLONE IS DRIFTING S OVER THE YUCATAN PENINSULA NEAR 19N88W WHILE UPPER TROUGHS RESIDE W AND E OF THE GULF BASIN. MAINLY DRY AND STABLE CONDITIONS PREVAIL ACROSS MOST OF THE GULF OF MEXICO THIS EVENING. A SURFACE TROUGH EXTENDING FROM FT MYERS FLORIDA THROUGH A DISSIPATING 1013 MB SFC LOW NEAR 26N83.5W TO 23N89W WAS DRIFTING S. THIS TROUGH SUPPORTED ISOLATED TO SCATTERED LOW TOPPED SHOWERS OVER THE EAST CENTRAL GULF. LIGHT NE WINDS PREVAILED OVER THE GULF N OF THE TROUGH AND OVER THE WESTERN PORTION OF THE BASIN. VARIABLE LIGHT WINDS WERE NOTED OVER THE SE GULF ALONG AND S OF THE SURFACE TROUGH. CARIBBEAN SEA... THE LEADING EDGE OF A MOISTURE SURGE IS SUPPORTING SCATTERED THUNDERSTORMS OVER THE N CENTRAL CARIBBEAN FROM 15N-22N BETWEEN 76W AND 81W WITH THE MOST INTENSE ACTIVITY OCCURRING OVER THE PROVINCES OF CIEGO DE AVILA AND CAMAGUEY IN CUBA WHERE WERE SIGNIFICANT LIGHTNING STRIKES OCCURRING OVER THE PAST HOUR. THE INTERACTION OF THIS MOIST AIRMASS WITH THE MONSOON TROUGH OVER PANAMA AND COSTA RICA SUPPORTED SCATTERED STRONG CONVECTION S OF 13N BETWEEN 78W AND 85W. ANOTHER AREA OF ENHANCED MOISTURE IS AHEAD OF A TROPICAL WAVE IS OVER THE E CARIBBEAN. MULTILAYERED CLOUDS WITH EMBEDDED SHOWER ACTIVITY WAS NOTED FROM 12N-15N BETWEEN 59W AND 65W...INCLUDING THE WINDWARD ISLANDS. ELSEWHERE...A SURFACE TROUGH EXTENDS FROM 21N85W TO 16N87W. NO DEEP CONVECTION IS NOTED. MAINLY MODERATE EASTERLY TRADE WINDS COVER THE CARIBBEAN E OF 83W. GENTLE TO MODERATE VARIABLE WINDS ARE OVER THE NW CARIBBEAN. OVER THE NEXT 24 HOURS CONVECTION WILL CONTINUE OVER THE SW CARIBBEAN. THE TROPICAL WAVE OVER THE CENTRAL ATLC WILL MOVE ACROSS THE LEEWARD ISLANDS LATER TONIGHT AND THURSDAY SUPPORTING CONVECTION OVER THE LESSER ANTILLES AND THE EASTERN CARIBBEAN. ...HISPANIOLA... SCATTERED THUNDERSTORMS WHICH DEVELOPED OVER THE INTERIOR OF HAITI AND THE DOMINICAN REPUBLIC HAVE WEAKENED CONSIDERABLY LEAVING MAINLY LOW AND MID LEVEL CLOUD COVER. A NEW ROUND OF THUNDERSTORMS ARE DEVELOPING OVER THE MONA PASSAGE AND MOVING OVER PUNTA CANA. THESE STORMS WILL SPREAD OVER THE EASTERN THIRD OF THE DOMINICAN REPUBLIC OVER THE NEXT SEVERAL HOURS BEFORE WEAKENING. AT THE UPPER LEVELS...A SHARP TROUGH WAS OVER THE WINDWARD PASSAGE AND HAITI AND MOVING SLOWLY E. THE INTERACTION OF THIS TROUGH AND AN APPROACHING TROPICAL WAVE CURRENTLY ALONG 60W COULD SUPPORT MORE ENHANCED SHOWER AND THUNDERSTORM ACTIVITY ON THURSDAY AS DEEP MOISTURE MAY BE IN PLACE ACROSS THE ISLAND. ATLANTIC OCEAN... A SHARP UPPER LEVEL TROUGH EXTENDS FROM OFF THE MID ATLANTIC COAST THROUGH 30N73W...THE SE BAHAMAS...HAITI TO A BASE NEAR 15N74W. THIS TROUGH SUPPORTED A 1013 MB LOW CENTERED NEAR 30N75W...WITH A SURFACE TROUGH EXTENDING FROM THE LOW TO THE FL PENINSULA NEAR 26N80W. DIFFLUENT FLOW EAST OF THE UPPER TROUGH SUPPORTED A BROAD AREA OF ENHANCED CLOUD COVER WITH ISOLATED MODERATE CONVECTION AND THUNDERSTORMS FROM 25N THROUGH 31N BETWEEN 65W AND 75W. A WEAK 1019 MB SURFACE HIGH IS CENTERED NEAR 27N56W. AN UPPER LEVEL CYCLONE IS CO-LOCATED OVER THIS HIGH PRODUCING UPPER LEVEL DIFFLUENCE THAT SUPPORTS SCATTERED MODERATE CONVECTION FROM 22N TO 25N BETWEEN 55W AND 60W. FARTHER EAST...A 1021 MB SURFACE HIGH CENTERED NEAR 27N32W SUPPORTS GENERALLY FAIR WEATHER OVER THE EASTERN ATLC. THREE TROPICAL WAVES ARE OVER THE TROPICAL N ATLC. PLEASE REFER TO THE TROPICAL WAVES SECTION FOR MORE DETAILS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB