000 AGXX40 KNHC 131902 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 302 PM EDT TUE SEP 13 2016 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS. ...GULF OF MEXICO... MODEL PREFERENCE: 12Z GFS BLEND WITH PREVIOUS OFFICIAL. HIGH CONFIDENCE. A HIGH PRES RIDGE OVER THE SOUTHERN UNITED STATES IS MAINTAINING GENTLE TO MODERATE WINDS OVER THE GULF. WEAK SURFACE LOW PRES OF 1011 MB IS CENTERED UNDER AN UPPER-LEVEL TROUGH OVER THE CENTRAL GULF NEAR 25N90W. A TROUGH EXTENDS NW FROM THE LOW TO THE FLORIDA COAST NEAR 27N82W. CURRENT BUOY READINGS AND RECENT ALTIMETER DATA INDICATE SEAS RANGING BETWEEN 1-3 FT. AN UPPER LEVEL TROUGH STRETCHES FROM THE FLORIDA BIG BEND SW TO THE BAY OF CAMPECHE. INSTABILITY ASSOCIATED WITH THIS TROUGH CONTINUES TO TRIGGER SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE ERN HALF OF THE GULF. THIS ACTIVITY IS EXPECTED TO PERSIST THROUGH WED. THE WEAK CENTRAL GULF LOW IS FORECAST TO DISSIPATE LATE TONIGHT OR ON WED...WHILE THE SURFACE TROUGH PRESENTLY ASSOCIATED WITH IT MOVES SLOWLY WESTWARD ACROSS THE WRN GULF. LITTLE CHANGE IS EXPECTED IN WINDS AND SEAS ACROSS THE BASIN THROUGH SAT NIGHT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 12Z GFS BLEND WITH PREVIOUS OFFICIAL. HIGH CONFIDENCE. WATER VAPOR IMAGERY INDICATES UPPER-LEVEL TROUGHING EXTENDING SW FROM HISPANIOLA OVER THE CARIBBEAN TO JUST E OF NICARAGUA. UPPER- LEVEL CONVERGENCE ASSOCIATED WITH THE TROUGH IS RESTRICTING CONVECTION OVER ALL OF THE CARIBBEAN WITH THE EXCEPTION OF THE FAR SW...WHERE THE MONSOON TROUGH WAS PROVIDING ENOUGH LOW-LEVEL CONVERGENCE TO PRODUCE ISOLATED CONVECTION. TROPICAL STORM IAN HAS WEAKENED THE RIDGE TO THE N OF THIS AREA. AS A RESULT...A RATHER RELAXED PRES GRADIENT SUPPORTS GENERALLY LIGHT TO GENTLE TRADES EXCEPT ALONG THE COAST OF COLOMBIA WHERE MODERATE TO OCCASIONALLY FRESH TRADES WERE PRESENT. WAVE MODEL GUIDANCE SHOW SWELL ASSOCIATED WITH IAN THAT ARE PROPAGATING INTO THE REGION WILL CONTINUE GRADUALLY DIMINISHING AS IAN CONTINUES NORTHWARD AWAY FROM THE TRPCL N ATLC. COMBINED SEA HEIGHTS OUTSIDE THE AFFECTED SWELL AREAS ARE EXPECTED TO BE IN THE RANGE OF 4-6 FT THROUGH THU. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: 12Z GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE... EXCEPT MEDIUM CONFIDENCE IN THE VICINITY OF FLORIDA AND THE BAHAMAS THROUGH WED. THE SURFACE TROUGH THAT MOVED THROUGH THE BAHAMAS THE PAST FEW DAYS HAS MOVED OVER THE FL PENINSULA. A WEAK 1011 MB LOW IS DRIFTING SLOWLY NNW IN THE TROUGH NEAR 29N81W. ANIMATED VISIBLE AND DOPPLER RADAR IMAGERY SHOW CONVECTION ASSOCIATED WITH THIS SYSTEM OVER THE FLORIDA PENINSULA AND ALONG THE FLORIDA E COAST TO THE W OF 79W. THE BAND OF CONVECTION ALONG THE FLORIDA COAST HAS BEEN PRODUCING SE WINDS OF 20 TO 25 KT. THE TROUGH AND LOW ARE FORECAST TO MOVE INLAND TOWARD THE FLORIDA PANHANDLE TONIGHT...ALLOWING WINDS AND SEAS ALONG THE E COAST OF FLORIDA TO SUBSIDE. OTHERWISE...RELATIVELY WEAK HIGH PRES WILL REMAIN IN PLACE TO THE N OF THIS AREA DURING THE NEXT FEW DAYS. GENTLE TO MODERATE E-SE WINDS ARE GENERALLY FORECAST THROUGH THE FORECAST PERIOD...WITH THE EXCEPTION OF FRESH E-SE WINDS FROM THE SE BAHAMAS TO HISPANIOLA AND NEAR THE WINDWARD PASSAGE. .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS II COLLABORATION CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANE WARNINGS.GOV/MARINE $$ .FORECASTER MCELROY. NATIONAL HURRICANE CENTER.