000 AXNT20 KNHC 031157 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT OCT 03 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...SPECIAL FEATURES... HURRICANE JOAQUIN IS CENTERED NEAR 25.6N 72.5W AT 03/1200 UTC OR ABOUT 140 NM NE OF SAN SALVADOR BAHAMAS AND ABOUT 570 NM SW OF BERMUDA MOVING NE AT 11 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 940 MB. MAXIMUM SUSTAINED WIND SPEED IS 110 KT WITH GUSTS TO 135 KT. NUMEROUS MODERATE TO ISOLATED STRONG CONVECTION IS FROM 22N TO 27N BETWEEN 70W AND 75W. SCATTERED MODERATE CONVECTION AND TSTMS ARE FROM 21N TO 27N BETWEEN 69W AND 76W AND FROM 17N TO 29N BETWEEN 60W AND 69W. THE OUTER RAINBANDS OF JOAQUIN REACHES THE NORTH-CENTRAL AND AND NE CARIBBEAN WHERE SCATTERED SHOWERS AND TSTMS ARE NOTED...INCLUDING EASTERN CUBA...WINDWARD PASSAGE...HISPANIOLA...PUERTO RICO AND THE LEEWARD ISLANDS. SEE LATEST 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. A 1005 MB NON-TROPICAL LOW IS CENTERED NEAR 26N52W OR ABOUT 740 NM ESE OF BERMUDA PRODUCING GALE-FORCE WINDS N OF THE CENTER. SHOWERS AND TSTMS ASSOCIATED WITH THIS LOW GREATLY DIMINISHED DURING THE LAST COUPLE OF HOURS AND MERGED WITH CONVECTION ASSOCIATED WITH A FRONTAL BOUNDARY JUST E OF IT. SCATTERED/ISOLATED SHOWERS AND TSTMS ARE WITHIN 140 NM OF THE LOW CENTER. EVEN THOUGH ENVIRONMENTAL CONDITIONS ARE FORECAST TO BE CONDUCIVE FOR THE LOW TO ACQUIRE MORE TROPICAL CHARACTERISTICS FOR ANOTHER DAY...DEVELOPMENT IS EXPECTED TO BE HINDERED BY STRONG UPPER-LEVEL WINDS ASSOCIATED WITH HURRICANE JOAQUIN. GALE WINDS ARE EXPECTED TO DIMINISH LATER TODAY. A MEDIUM CHANCE EXISTS FOR THE LOW TO DEVELOP INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... A TROPICAL WAVE CAME OFF THE AFRICAN COAST FRIDAY MORNING AND NOW IS MOVING OVER THE CAPE VERDE ISLANDS WITH AXIS APPROXIMATELY ALONG 24W. THE WAVE IS EMBEDDED IN A MODERATE MOIST ENVIRONMENT AT THE LOWER LEVELS THAT ENHANCES SCATTERED SHOWERS FROM 03N TO 09N BETWEEN 21W AND 28W. CONVECTION IN THE NORTHERN WAVE ENVIRONMENT IS BEING INHIBITED BY THE PRESENCE OF DRY AIR AND DUST AS INDICATED BY METEOSAT ENHANCED IMAGERY. MODEL GUIDANCE INDICATE THIS WAVE WILL MERGE WITH THE TROPICAL WAVE AHEAD OF IT WITHIN THE NEXT 24 HOURS. A TROPICAL WAVE IS OVER THE CENTRAL ATLC WITH TILTED AXIS EXTENDING FROM 16N34W TO A 1009 MB LOW NEAR 09N30W...MOVING W AT 5-10 KT. CIRA LAYER PRECIPITABLE WATER IMAGERY SHOW THE WAVE IS EMBEDDED IN A MODERATE TO HIGH MOIST ENVIRONMENT FROM THE SURFACE TO NEARLY 700 MB THAT ALONG WITH MIDDLE TO UPPER LEVEL DIFFLUENCE IN THE WAVE REGION SUPPORT SCATTERED MODERATE CONVECTION AND TSTMS FROM 03N TO 13N BETWEEN 29W AND 37W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF WEST AFRICA NEAR 11N15W TO 08N22W TO A 1009 MB LOW NEAR 09N30W TO 09N37W. FOR CONVECTION INFORMATION REFER TO THE TROPICAL WAVES SECTION. ...DISCUSSION... GULF OF MEXICO... BROAD SURFACE LOW PRESSURE ASSOCIATED WITH HURRICANE JOAQUIN IN THE SW N ATLC COVERS THE BASIN AND PROVIDE N-NW WIND FLOW OF 15- 20 KT ACROSS THE GULF...THE STRONGEST WINDS BEING IN THE NORTHERN GULF DUE TO A TIGHT PRESSURE GRADIENT WITH A BROAD RIDGE COVERING THE CENTRAL AND NE U.S. WITH THE PASSAGE OF A COLD FRONT THESE LAST TWO DAYS...DRY STABLE LOW-LEVEL AIR COVERS THE BASIN WHILE WATER VAPOR IMAGERY CONTINUE TO SHOW VERY DRY AIR ALOFT...THUS SUPPORTING FAIR WEATHER CONDITIONS AND CLEAR SKIES. LOW PRESSURE AND SIMILAR WEATHER CONDITIONS WILL PREVAIL THE NEXT THREE DAYS WHILE JOAQUIN TAKES A NNE TRACK IN THE ATLC. WINDS ARE EXPECTED TO BECOME LESS THAN 15 KT BY MONDAY. CARIBBEAN SEA... THE OUTER RAINBANDS OF MAJOR HURRICANE JOAQUIN OVER THE SW N ATLC CONTINUE TO AFFECT THE NORTH-CENTRAL AND THE NE CARIBBEAN WHERE SCATTERED SHOWERS AND TSTMS ARE NOTED...INCLUDING EASTERN CUBA...WINDWARD PASSAGE...HISPANIOLA...PUERTO RICO AND THE LEEWARD ISLANDS. IN TERMS OF WIND...SW TO W WINDS OF 20 TO 25 KT ARE N OF 18N BETWEEN 73W AND 78W...INCLUDING THE WINDWARD PASSAGE WITH SEAS TO 8 FT IN THE WINDWARD PASSAGE. W-NW WIND FLOW OF 15 KT IS OVER THE NW CARIBBEAN WHILE S-SE WIND FLOW OF SIMILAR MAGNITUDE COVERS THE EASTERN BASIN. A SURFACE TROUGH IS OVER THE NW CARIBBEAN WATERS FROM 21N78W SW TO COASTAL WATERS OF HONDURAS NEAR 16N87W ENHANCING SCATTERED SHOWERS AND TSTMS WITHIN 120 NM EITHER SIDE OF THE TROUGH. SHALLOW MOISTURE OVER THE S AND SE CARIBBEAN ALONG WITH DIFFLUENCE ALOFT SUPPORT ISOLATED SHOWERS. LOOKING AHEAD...AREAS OF CONVECTIVE PRECIPITATION ARE EXPECTED TO CONTINUE IMPACTING THE NORTHERN CARIBBEAN THROUGH TONIGHT AS JOAQUIN TRACKS NORTHWARD. SURFACE WINDS ARE EXPECTED TO DIMINISH BY EARLY SUNDAY. ...HISPANIOLA... CURRENTLY...THE OUTER CONVECTIVE BANDS OF HURRICANE JOAQUIN IN THE SW N ATLC ARE PRODUCING SCATTERED TO ISOLATED SHOWERS OVER HISPANIOLA. IN TERMS OF WIND...SW TO W WINDS OF 20 TO 25 KT ARE N OF 18N BETWEEN 73W AND 78W...INCLUDING THE WINDWARD PASSAGE WITH SEAS TO 8 FT IN THE WINDWARD PASSAGE. RAINSHOWERS ARE EXPECTED TO CONTINUE IMPACTING THE ISLAND THROUGH TONIGHT AS JOAQUIN TRACKS NORTHWARD. SURFACE WINDS ARE EXPECTED TO DIMINISH BY EARLY SUNDAY. ATLANTIC OCEAN... THE MAIN FEATURE ACROSS THE ATLANTIC IS MAJOR HURRICANE JOAQUIN OVER THE SW N ATLC. PLEASE REFER TO THE SPECIAL FEATURES SECTION ABOVE FOR MORE DETAILS. THE SECOND AREA OF INTEREST IS A 1005 MB NON-TROPICAL LOW CENTERED NEAR 26N52W OR ABOUT 738 NM ESE OF BERMUDA THAT IS PRODUCING GALE-FORCE WINDS N OF IT. SCATTERED/ISOLATED SHOWERS AND TSTMS ARE WITHIN 140 NM OF THE LOW CENTER. A MEDIUM CHANCE EXISTS FOR THE LOW TO DEVELOP INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. SEE SPECIAL FEATURES SECTION ABOVE FOR FURTHER INFORMATION. NW OF JOAQUIN...THE TAIL OF A STATIONARY FRONT IS ANALYZED FROM 30N79W TO 28N79W THAT ENHANCES SHOWERS AND TSTMS WITHIN 45 NM E OF IT. OVER PORTIONS OF THE NE AND CENTRAL ATLC...A COLD FRONT EXTENDS FROM 30N25W TO 25N37W TO 25N44W WHERE IT TRANSITIONS TO A STATIONARY FRONT TO 27N48W. SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS ARE WITHIN 120 NM S OF THE FRONTAL BOUNDARY. A WEAK SURFACE RIDGE PREVAILS FARTHER E IN THE NE ATLANTIC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR