000 AGXX40 KNHC 250744 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 344 AM EDT THU AUG 25 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: EUROPEAN GLOBAL MODELS. HIGH CONFIDENCE THROUGH SAT...THEN LOW CONFIDENCE SUN-MON. A RIDGE AXIS EXTENDS ACROSS THE NORTHERN PART OF THE REGION FROM SOUTHERN GEORGIA TO SOUTHERN TEXAS. SCATTEROMETER DATA AND SURFACE OBS INDICATE GENTLE TO MODERATE EASTERLY WINDS PREVAIL S OF THE RIDGE AXIS ACROSS MOST OF THE GULF...WITH SEAS RUNNING 2-3 FT. EXPECT THE RIDGE AXIS TO GRADUALLY LIFT NORTHWARD AND WEAKEN SLIGHTLY THE NEXT COUPLE OF DAYS...WITH GENTLE TO MODERATE WINDS CONTINUING THROUGH SAT. UNCERTAINTY INCREASES SIGNIFICANTLY OVER THE EASTERN GULF SUN AND MON AS A STRONG TROPICAL WAVE AND AN ASSOCIATED LOW CURRENTLY NW OF PUERTO RICO APPROACHES S FLA AND THE FLORIDA KEYS. THE GFS AND EUROPEAN GLOBAL MODELS OFFER WIDELY DIVERGENT SOLUTIONS...SO CONFIDENCE IS LOW. EXPECT OR AT LEAST HOPE SOME CONSENSUS BETWEEN MODELS WILL BEGIN TO EMERGE THE NEXT DAY OR SO...BUT UNTIL THEN WILL LEAN TOWARD EUROPEAN MODELS AS PRIMARY GUIDANCE WHICH IS CLOSER TO NHC PROVISIONAL FCST. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE. LOWER PRESSURE NORTH AND NORTHEAST OF THE AREA...ASSOCIATED WITH A STRONG TROPICAL WAVE WITH AN AREA OF LOW PRESSURE CENTERED NW OF PUERTO RICO AND TS GASTON IN THE CENTRAL ATLANTIC...IS KEEPING A WEAK PRESSURE GRADIENT ACROSS THE REGION. LIGHT TO GENTLE WINDS ARE INDICATED FROM THE LATEST SCATTEROMETER DATA AND BUOY OBS. EXPECT THE PRESSURE GRADIENT TO REMAIN BENIGN THE NEXT SEVERAL DAYS ACROSS THE REGION AS MOST OF THE TROPICAL ACTIVITY OCCURS N OF 20N. LONG PERIOD N-NE SWELL GENERATED BY GASTON IS EXPECTED TO PROPAGATE INTO THE TROPICAL WATERS N OF 18N E OF 57W FRI. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. LOW CONFIDENCE. SCATTEROMETER DATA SHOWS THE REMNANT CIRCULATION OF WHAT USED TO BE FIONA HAS DETERIORATED INTO A TROUGH NE OF THE BAHAMAS. A STRONG TROPICAL WAVE WITH AN ASSOCIATED SURFACE LOW IS LOCATED NW OF PUERTO RICO NEAR 21N69W. AN ASCAT PASS OVER THIS DISTURBANCE AT 0200 UTC SHOWED A SHARP TROUGH WITH 30-35 KT WINDS N OF PUERTO RICO NEAR 20N67W. THE SATELLITE IMAGERY SHOWS A MASS OF DISORGANIZED DEEP CONVECTION DISPLACED SE OF THE TROUGH AXIS. EXPECT A SMALL AREA OF GALE FORCE WINDS TO PERSIST TODAY NE OF THE LOW CENTER... BUT CONTRARY TO PREVIOUS FORECAST IT APPEARS THE TROUGH WILL OPEN UP A BIT AS IT APPROACHES THE BAHAMAS...WITH MAX WINDS SUBSIDING JUST A BIT TO 30 KT. THIS IS IN RESPONSE TO A SURFACE TROUGH N-NE OF THE LOW WHICH WILL WEAKEN THE PRES GRADIENT OF THE NE SIDE OF THE LOW. EXPECT MAX SEAS TO CONTINUE AT 10-12 FT IN THE AREA OF HIGHEST WINDS. SO WILL TAPER BACK THE GALE WARNING TO ONLY INCLUDE TODAY BASED ON THE BEST AVAILABLE MODEL GUIDANCE. THE GFS TRACK IS NOW CLOSER TO THE ECMWF SO SOME CONSENSUS IS POSSIBLE BUT CONSIDERABLE UNCERTAINTY EXISTS REGARDING INTENSITY OF THE LOW AS IT TRACKS ACROSS THE BAHAMAS TOWARDS SOUTHERN FLORIDA. LARGE SWELL ASSOCIATED WITH GASTON WILL REACH FORECAST WATERS BETWEEN 55-60W FRI NIGHT AND CONTINUE THROUGH THE WEEKEND...TO AFFECT ZONE AMZ115 SUN NIGHT AND MON. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS II COLLABORATION CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... .AMZ121...ATLANTIC FROM 22N TO 27N BETWEEN 65W AND 70W... GALE WARNING EARLY TODAY. .AMZ125...ATLANTIC S OF 22N BETWEEN 65W AND 70W INCLUDING PUERTO RICO TRENCH... GALE WARNING EARLY TODAY. $$ *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 MUNDELL. NATIONAL HURRICANE CENTER.