000 AXNT20 KNHC 041746 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN OCT 04 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1630 UTC. ...SPECIAL FEATURES... HURRICANE JOAQUIN CENTERED NEAR 31.6N 66.6W AT 04/1800 UTC OR 109 NM SW OF BERMUDA MOVING NNE AT 13 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 957 MB. MAXIMUM SUSTAINED WIND SPEED IS 90 KT WITH GUSTS TO 110 KT. NUMEROUS MODERATE AND SCATTERED STRONG CONVECTION IS WITHIN 150 NM IN THE NE SEMICIRCLE AND 45 NM IN THE SW SEMICIRCLE. SCATTERED MODERATE CONVECTION IS ELSEWHERE WITHIN 360 NM IN THE NE SEMICIRCLE. A TROUGH IS SE OF THE HURRICANE FROM 27N65W TO 24N68W TO 21N74W WITH SCATTERED MODERATE CONVECTION WITHIN 30-60 NM E OF THE TROUGH AXIS. JOAQUIN IS FORECAST TO WEAKEN WHILE MOVING TO 34.8N 64.8W BY 24 HOURS...THEN TO 36.6N 62.7W BY 48 HOURS. SEE LATEST INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 KNHC AND THE LATEST FULL NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A PAIR OF TROPICAL WAVES OVER THE E CENTRAL ATLC HAVE MERGED THIS MORNING WITH THE PRIMARY AXIS EXTENDING FROM 20N35W TO LOW PRES NEAR 10.5N38W 1010 MB. PLENTIFUL CONVECTION IS PRESENT WITH THESE FEATURES WITH SCATTERED MODERATE FROM 07N-15N BETWEEN 31W- 44W...AND FROM 14N-18N BETWEEN 30W-35W. RECENT SCATTEROMETER PASSES MISSED THE TROPICAL WAVE AND LOW...HOWEVER A RECENT ALTIMETER PASS DID MEASURE SEAS TO 8 FT IN THE SE QUADRANT OF THE LOW. ACCORDING TO THE LATEST GLOBAL MODEL GUIDANCE...THE LOW IS FORECAST TO MOVE TO NEAR 14N43W WHILE WEAKENING BY 24 HOURS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM NEAR 08N24W TO 14N33W TO LOW PRES NEAR 10.5N38W 1010 MB TO 09N49W. THE ITCZ AXIS EXTENDS FROM 09N49W TO 08N59W. ASIDE FROM CONVECTION OCCURRING IN ASSOCIATION WITH THE LOW AND AN ACCOMPANYING TROPICAL WAVE... SCATTERED MODERATE CONVECTION IS FROM 05N-08N BETWEEN 29W-34W... FROM 10N-13N BETWEEN 47W-51W...AND FROM 08N-10N BETWEEN 50W-53W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL ANTICYCLONE PREVAILS ACROSS THE SW GULF OF MEXICO NEAR 21N96W. VERY DRY AND STABLE AIR COVERS THE MAJORITY OF THE GULF S OF 26N. A COMPLEX UPPER LEVEL LOW IS LOCATED OVER SOUTHERN GEORGIA NEAR THE NORTHERN FLORIDA BORDER NEAR 31N83W. A SERIES OF TROUGHS CONTINUE TO ROTATE AROUND THIS UPPER LOW... BOTH ALOFT AND AT THE SURFACE...WITH ISOLATED TO SCATTERED SHOWERS ACCOMPANYING EACH TROUGH. GENTLE TO MODERATE WINDS WILL PREVAIL THROUGH THE NEXT 48 HOURS...EXCEPT IN THE NE GULF WHERE THEY WILL OCCASIONALLY INCREASE TO MODERATE TO FRESH WITH EARLY SEASON COLD AIR ADVECTION IN PLACE. SEAS WILL BE 1-3 FT ACROSS THE SW HALF OF THE GULF AND 3-5 FT ACROSS THE NE HALF OF THE GULF. CARIBBEAN SEA... AN UPPER LEVEL TROUGH IS MOVING THROUGH THE NW CARIBBEAN FROM CENTRAL CUBA TO THE GULF OF HONDURAS SUPPORTING A SURFACE TROUGH WHICH EXTENDS FROM NEAR THE WINDWARD PASSAGE TO NE HONDURAS. NO SIGNIFICANT CONVECTION IS OBSERVED NEAR THE TROUGH EXCEPT FOR SOME ISOLATED TSTMS NEAR THE WINDWARD PASSAGE. AN UPPER LEVEL ANTICYCLONE IS LOCATED IN THE SW CARIBBEAN NEAR 12N79W. STRONG UPPER LEVEL NORTHERLY FLOW COVERS THE BASIN E OF 72W. THE SURFACE TROUGH WILL SLIDE TO THE E DURING THE NEXT 24 HOURS GRADUALLY LOSING DEFINITION. LIGHT TO MODERATE WINDS WILL PREVAIL ACROSS THE BASIN EXCEPT IN THE S CENTRAL WATERS WHERE WINDS WILL BE MODERATE TO FRESH...INCREASING TO FRESH TO STRONG LATE MON NIGHT INTO TUE MORNING. SEAS WILL BE 1-3 FT ACROSS THE NW CARIBBEAN...WITH 4-7 FT ELSEWHERE EXCEPT BUILDING TO 7-9 FT IN THE S CENTRAL WATERS. ...HISPANIOLA... WESTERLY FLOW ASSOCIATED WITH THE CIRCULATION OF JOAQUIN WILL CONTINUE TO BRING ISOLATED SHOWERS AND THE OCCASIONAL ISOLATED TSTM ACROSS THE ISLAND. A SURFACE TROUGH TO THE W OF THE ISLAND WILL APPROACH THE AREA OVER THE NEXT 12-24 HOURS SUPPORTING ADDITIONAL CONVECTION. ATLANTIC OCEAN... HURRICANE JOAQUIN CONTINUES TO DOMINATE MUCH OF THE CONDITIONS ACROSS THE SW N ATLC. PLEASE REFER TO THE SPECIAL FEATURES SECTION FOR ADDITIONAL DETAILS ON JOAQUIN. A SURFACE TROUGH EXTENDS FROM 1001 MB LOW PRES LOCATED OFFSHORE OF THE SOUTH CAROLINA LOW COUNTRY NEAR 32N79W TO THE SE TO NEAR 28N73W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING NEAR THE TROUGH. ADDITIONAL WEAK TROUGHS ARE FORECAST TO ROTATE THROUGH THE BASIN DURING THE NEXT 24-48 HOURS AROUND AN UPPER LEVEL LOW THAT IS CURRENTLY NEAR THE SOUTHERN GEORGIA/NORTHERN FLORIDA BORDER NEAR 31N83W. OVER THE NEXT 24-48 HOURS...THE CIRCULATION OF JOAQUIN WILL PULL AWAY FROM THE DISCUSSION WATERS WITH DECREASING INFLUENCES ON THE SW N ATLC. TO THE E OF 60W...1008 MB LOW PRES IS NEAR 27N53W WITH AN ELONGATED SURFACE TROUGH REACHING FROM 31N59W TO THE LOW TO 25N43W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 180 NM IN THE SW QUADRANT OF THE LOW. RECENT SCATTEROMETER DATA SHOWED FRESH TO STRONG WINDS ON EITHER SIDE OF THE LOW/TROUGH. THE LOW IS FORECAST TO MOVE ENE AROUND 10 KT DURING THE NEXT 24-48 HOURS. WEAK 1017 MB HIGH PRES IS LOCATED S- SW OF THE LOW NEAR 21N55W AS INDICATED BY RECENT SCATTEROMETER DATA. A DISSIPATING COLD FRONT IS LOCATED OVER THE NE WATERS FROM NEAR 32N14W TO 21N33W. A SURFACE RIDGE IS BUILDING IN BEHIND THE FRONT ACCOMPANYING 1019 MB HIGH PRES NEAR 25N29W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LEWITSKY