000 AXNT20 KNHC 021748 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI OCT 02 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 1715 UTC. ...SPECIAL FEATURES... HURRICANE JOAQUIN IS CENTERED NEAR 23.8N 74.8W AT 02/1800 UTC OR ABOUT 10 NM N OF RUM CAY BAHAMAS AND ABOUT 20 NM SW OF SAN SALVADOR BAHAMAS MOVING N AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 942 MB. MAXIMUM SUSTAINED WIND SPEED IS 115 KT WITH GUSTS TO 140 KT. NUMEROUS MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 120 NM OF CENTER WITH SCATTERED MODERATE CONVECTION ELSEWHERE FROM 18N-26N BETWEEN 70W-79W. 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 1003 MB LOW IS CENTERED NEAR 27N53W AND CURRENTLY SUPPORTED ALOFT BY AN UPPER LEVEL LOW TO THE WEST CENTERED NEAR 27N60W. LYING WITHIN A SLIGHTLY DIFFLUENT ENVIRONMENT ALOFT AND SOUTHWESTERLY FLOW SCATTERED MODERATE CONVECTION IS OCCURRING GENERALLY EAST OF THE LOW CENTER FROM 24N-28N BETWEEN 46W-52W. THE SYSTEM IS GENERATING NEAR GALE TO GALE FORCE WINDS WITHIN 180 NM OF CENTER IN THE NORTHERN SEMICIRCLE. IN ADDITION...A HIGH CHANCE EXISTS OF THE LOW DEVELOPING INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 11N29W TO 19N31W MOVING W AT 5-10 KT. THE WAVE COINCIDES WITH 700 MB TROUGHING BETWEEN 25W-35W AND A MAXIMUM IN 850 MB RELATIVE VORTICITY FOCUSED AROUND A 1009 MB LOW CENTERED AT THE SOUTHERN EXTENT OF THE WAVE AXIS NEAR 11N29W. SCATTERED MODERATE CONVECTION IS FROM 13N-17N BETWEEN 26W-32W WITH ISOLATED MODERATE CONVECTION OCCURRING FROM 07N-12N BETWEEN 27W-32W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM A 1010 MB LOW CENTERED NEAR 08N18W INTO A 1009 MB LOW ASSOCIATED WITH A TROPICAL WAVE ALONG 30W TO 08N38W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS FROM 08N-15N BETWEEN 15W-21W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 02N-06N BETWEEN 18W-28W. ELSEWHERE...A PORTION OF LOW-LEVEL ENERGY...PREVIOUSLY ANALYZED AS A TROPICAL WAVE...HAS WEAKENED AND REMAINS AS A 1012 MB LOW CENTERED NEAR 14N40W WITH A SURFACE TROUGH EXTENDING N-NE TO 20N36W. NO SIGNIFICANT DEEP CONVECTION IS OCCURRING WITH THIS FEATURE. ...DISCUSSION... GULF OF MEXICO... A VIGOROUS MIDDLE TO UPPER LEVEL LOW IS NOTED ON WATER VAPOR IMAGERY CENTERED OVER ALABAMA WITH A TROUGH AXIS EXTENDING SOUTHWARD OVER THE EASTERN GULF ALONG 88W TO THE YUCATAN PENINSULA. THE TROUGHING SUPPORTS A COLD FRONT EXTENDING ACROSS THE SOUTHERN FLORIDA PENINSULA TO THE NORTHERN COAST OF THE YUCATAN PENINSULA NEAR 22N88W TO JUST EAST OF THE CHIVELA PASS IN SOUTHERN MEXICO NEAR 18N94W. VERY DRY CONDITIONS ALOFT PREVAIL AND ARE PROMOTING MOSTLY CLEAR SKIES ACROSS A MAJORITY OF THE GULF THIS AFTERNOON WITH MODERATE TO FRESH NORTHERLY WINDS NORTH OF THE FRONT. ONLY A FEW ISOLATED SHOWERS ARE OCCURRING WITHIN 60 NM EITHER SIDE OF THE FRONT E OF 83W... INCLUDING INLAND PORTIONS OF THE WESTERN YUCATAN PENINSULA. NORTHERLY FLOW IS EXPECTED TO PERSIST THROUGH SATURDAY WITH MODERATE TO FRESH BREEZE CONDITIONS ARE EXPECTED TO SHIFT SLIGHTLY MORE NORTHWESTERLY INTO SUNDAY. CARIBBEAN SEA... DUE TO THE PRESENCE OF HURRICANE JOAQUIN ACROSS THE CENTRAL BAHAMAS...NORMAL TRADE WIND FLOW HAS BEEN DISRUPTED WITH GENTLE TO MODERATE SOUTHERLY WINDS GENERALLY E OF 72W AND GENTLE TO MODERATE WEST-SOUTHWEST WINDS W OF 72W. RECENT SCATTEROMETER PASSES CONFIRM THIS FLOW WITH A WEAKENING COLD FRONT ANALYZED ACROSS WESTERN CUBA...THE YUCATAN CHANNEL AND PENINSULA. THE FRONT IS PRODUCING A FEW ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THE BOUNDARY. MOST OF THE MOISTURE HOWEVER IS NOTED ACROSS THE NORTH-CENTRAL CARIBBEAN AND PORTIONS OF THE NW CARIBBEAN AS OUTER CONVECTIVE BANDS ASSOCIATED WITH JOAQUIN. THE SCATTERED SHOWERS AND TSTMS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF A LINE STRETCHING FROM THE CENTRAL COAST OF HONDURAS NEAR 16N87W TO THE WINDWARD PASSAGE AND ACROSS HISPANIOLA. AS JOAQUIN IS FORECAST TO TRACK NORTHWARD DURING THE NEXT 24 TO 48 HOURS...ONGOING CONVECTION IS EXPECTED TO GRADUALLY DIMINISH BY SUNDAY WITH TRADE WIND FLOW RE-ESTABLISHING ITSELF ACROSS THE EASTERN TWO-THIRDS OF THE BASIN BY LATE SUNDAY INTO MONDAY. ...HISPANIOLA... CURRENTLY...THE OUTER CONVECTIVE PRECIPITATION BANDS OF HURRICANE JOAQUIN EXTEND ACROSS THE ISLAND AS SCATTERED SHOWERS AND TSTMS GENERALLY N OF 17N BETWEEN 68W-76W. THE CONVECTION IS EXPECTED TO PERSIST DURING THE NEXT 24 HOURS AS THE HURRICANE LINGERS NORTH OF THE ISLAND WHILE BEGINNING TO SLOWLY TRACK NORTHWARD. ATLANTIC OCEAN... THE MAIN FEATURE ACROSS THE SW NORTH ATLC IS HURRICANE JOAQUIN. WHILE JOAQUIN REMAINS THE FOCUS...THE AREA OF LOWER PRESSURE VALUES EXTENDS NORTHWESTWARD ACROSS FLORIDA AND SOUTHEASTERN GEORGIA AND SOUTH CAROLINA. A VIGOROUS MIDDLE TO UPPER LEVEL LOW IS CENTERED OVER ALABAMA AND SUPPORTS A 1000 MB LOW NEAR 28N80W WITH A STATIONARY FRONT EXTENDING N-NE TO BEYOND 32N79W AND A COLD FRONT ACROSS SOUTH FLORIDA INTO THE SE GULF OF MEXICO. MOST OF THE PRECIPITATION ASSOCIATED WITH THE FRONT IS OCCURRING N OF 28N W OF 77W AS SCATTERED SHOWERS AND TSTMS IN THE VICINITY OF THE STATIONARY FRONT. HURRICANE JOAQUIN IS EXPECTED TO TRACK GENERALLY NORTH-NORTHEASTWARD THROUGH SUNDAY AND NORTH OF THE DISCUSSION AREA THEREAFTER. FARTHER EAST...THE OTHER SPECIAL FEATURE...A 1003 MB LOW CENTERED NEAR 27N53W...CONTINUES TO DEVELOP TROPICAL CHARACTERISTICS. HOWEVER...REGARDLESS OF POTENTIAL TROPICAL CYCLONE DEVELOPMENT...NEAR GALE TO GALE FORCE WINDS ARE OCCURRING WITHIN 180 NM OF CENTER IN THE NORTHERN SEMICIRCLE. OTHERWISE...THE EASTERN ATLC IS UNDER THE INFLUENCE OF A STATIONARY FRONT EXTENDING FROM 32N29W TO 27N47W. ISOLATED SHOWERS AND TSTMS ARE OCCURRING WITHIN 240 NM EITHER SIDE OF THE BOUNDARY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN