000 AGXX40 KNHC 250722 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 322 AM EDT MON AUG 25 2014 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: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. NWPS BLEND USED FOR WAVE PARAMETERS. MEDIUM CONFIDENCE. AN UNUSUALLY VIGOROUS COLD FRONT FOR LATE AUGUST HAS MOVED INTO THE NE GULF OF MEXICO WITH WINDS AT SGOF1...AN ELEVATED PLATFORM...REACHING 24 KT AT 06Z. THE GEFS SHOWS A 20-30 PERCENT CHANCE OF WINDS AT THE ADVISORY LEVEL OF 20-25 KT THROUGH THIS MORNING IN THE COASTAL WATERS FORECAST AREA. WINDS ARE FORECAST BY BOTH THE GFS AND ECMWF TO DIMINISH SLIGHTLY THIS AFTERNOON AND EVENING BUT THEY RETURN TO NEAR ADVISORY LEVEL AROUND 06Z TUE AS A SECONDARY SURGE OF E-NE WINDS MOVES THROUGH THE REGION. THE GEFS SHOWS A 50-60 PERCENT CHANCE OF WINDS AT ADVISORY CRITERIA IN THE COASTAL WATERS AND A 30-40 PERCENT CHANCE IN THE OFFSHORES. THE GFS IS SLIGHTLY MORE AGGRESSIVE HERE THAN THE ECMWF...BUT SEEMS TO BE PANNING OUT BEST COMPARED TO THE CURRENT CONDITIONS REPORTED BY SURFACE OBSERVATIONS AND ASCAT. THE FRONT WILL DEGENERATE TO A TROUGH BY THIS EVENING. THIS TROUGH WILL MEANDER FROM NEAR THE STRAITS OF FLORIDA TO NEAR BROWNSVILLE TEXAS TUE THROUGH THU MORNING. THE GFS WAS USED TO ADJUST THE GRIDS ALONG WITH THE MWW3 WHICH WAS FAVORED OVER THE LOWER WAVE HEIGHTS OF THE NWPS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. NWPS BLENDED WITH OFFICIAL FOR WAVE PARAMETERS. MEDIUM CONFIDENCE. THE NORMALLY STRONG TRADE WINDS IN THE CENTRAL CARIBBEAN HAVE DIMINISHED SINCE THE SUBTROPICAL RIDGE TO THE N HAS RETREATED E DUE TO CRISTOBAL. TRADES ARE NOT EXPECTED TO RETURN TO ADVISORY CRITERIA UNTIL TUE NIGHT AS CRISTOBAL LIFTS N OF THE BAHAMAS AND THE SUBTROPICAL RIDGE BUILDS TO ITS S. THIS WILL ALLOW THE PRESSURE GRADIENT THE STRENGTHEN OVER THE CENTRAL CARIBBEAN. FRESH TO STRONG WINDS ARE EXPECTED TO BE CONFINED TO CENTRAL WATERS IN THE LATE NIGHT THROUGH MORNING HOURS TUE NIGHT THROUGH THE END OF THE PERIOD FRI NIGHT. WHILE THE ECMWF IS PREFERRED WITH THE TRACK OF T.D. CRISTOBAL AND THE PATTERN TO THE N...THE GFS GENERALLY DOES A BETTER JOB WITH THESE DIURNALLY DRIVEN WINDS. THE GFS IS STRONGER THAN THE ECMWF WITH THE WINDS IN THE CENTRAL CARIBBEAN. WILL ADJUST THE GRIDS TO THE GFS HERE. THE GFS AND ECMWF ARE IN REASONABLE AGREEMENT WITH AN ACTIVE TROPICAL WAVE EXPECTED TO MOVE INTO THE TROPICAL N ATLC WATERS WED NIGHT...THE EASTERN CARIBBEAN BY EARLY FRI. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: 00Z ECMWF BLENDED WITH PREVIOUS OFFICIAL. EC WAVE/NWPS USED FOR WAVE PARAMETERS. MEDIUM CONFIDENCE. THE GFS AND ECMWF HAVE TRENDED TO THE EAST WITH THE SHORT TERM FORECAST FOR CRISTOBAL. THE GFS BECOMES SIGNIFICANTLY FASTER THAN THE PREVIOUS NHC FORECAST AFTER FORECAST HOUR 24. THE OFFICIAL NHC FORECAST IS CLOSEST TO THE 00Z ECMWF...WITH THE ECMWF ON THE SLOW END OF THE 00Z GUIDANCE ENVELOPE. ACCORDING TO THE ASCAT PASSES FROM AROUND 02Z...CRISTOBAL HAS NOT MOVED MUCH IN THE PAST 6-12 HOURS. THIS LENDS CREDENCE TO THE ECMWF FORECAST. WILL USE THE 00Z ECMWF TO ADJUST THE FORECAST OUTSIDE OF THE EXPECTED AREA OF TROPICAL STORM FORCE WINDS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... .AMZ113...ATLANTIC FROM 27N TO 31N BETWEEN 70W AND 77W... TROPICAL STORM WARNING TONIGHT INTO TUE NIGHT. .AMZ119...ATLANTIC FROM 22N TO 27N E OF BAHAMAS TO 70W... TROPICAL STORM WARNING EARLY TODAY INTO TONIGHT. $$ *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 SCHAUER. NATIONAL HURRICANE CENTER.