000 AGXX40 KNHC 211904 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 204 PM EST SAT DEC 21 2013 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: PREVIOUS/OFFICIAL FORECAST BLENDED WITH LATEST GFS. PREVIOUS FORECAST AND MWW3 BLEND USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. S-SE WINDS ON THE WESTERN EDGE OF RIDGING EXTENDING FROM CENTRAL ATLC HIGH PRES RANGES FROM A GENTLE BREEZE IN THE EASTERN GULF TO A STRONG BREEZE IN THE NW GULF. LATE MORNING/EARLY AFTERNOON ELEVATED PLATFORMS/OBSERVATIONS IN THE NW GULF HAVE BEEN REPORTING 30-35 KT WITH WINDS UP TO 30 KT LIKELY AT 10M. THE 12Z ECMWF SHOWS A LARGE AREA OF SOLID 30 KT WINDS IN THE NW GULF. ALSO...BUOY OBSERVATIONS FROM THIS MORNING INDICATED 8-11 FT SEAS IN THE NW GULF...ABOUT 2 FT HIGHER THAN AVAILABLE WAVE GUIDANCE. THE RIDGING WILL GRADUALLY BREAK DOWN AND SHIFT E THROUGH THE REST OF TODAY AS THE NEXT COLD FRONT APPROACHES THE TEXAS COAST. THAT FRONT IS FORECAST TO MOVE INTO THE NW GULF COASTAL WATERS TONIGHT...BRIEFLY STALLING OUT FROM S CENTRAL LOUISIANA TO NE MEXICO INTO SUN MORNING. A REINFORCING SURGE OF NORTHERLY WINDS AND COLD AIR ARRIVES IN THE NW PORTION LATE SUN INTO MON. THE LATEST RUNS OF THE GFS AND ECMWF NOW AGREE ON THE ONSET OF GALE FORCE WINDS IN THE SW GULF (GMZ023) COMMENCING AT 12Z MON MORNING...WITH THE GFS HOLDING ONTO THE GALE 6-12 HOURS LONGER BY ENDING IT AT 12Z TUE. THE 12Z GFS ALSO PUSHES GALE FORCE WINDS INTO GMZ025 TUE MORNING. 09Z SREF 34 KT PROBABILITIES (15Z NOT AVAILABLE YET) ARE NOW AS HIGH AS 99 PERCENT BY 21 UTC MON AND ARE STILL AROUND 30 PERCENT BY THE END OF ITS RUN AT 12Z TUE. THE 12Z GEFS PROBABILITIES SHOW A CHANCE OF GALES FROM 12Z MON UNTIL 18Z TUE...AS HIGH AS A 100 PERCENT CHANCE OF GALES AT 00Z TUE...WITH HIGH PROBABILITIES ALSO SPREADING INTO GMZ025. THE LATEST GFS WAS BLENDED WITH THE PREVIOUS OFFICIAL FORECAST WHICH RESULTED IN GALES ONLY IN ZONE GMZ023 ALTHOUGH IT MAY NEED TO BE EXTENDED TO GMZ025 IF TRENDS CONTINUE. FRESH TO STRONG NORTHERLY WINDS WILL SPREAD ACROSS THE REMAINDER OF THE GULF BEHIND THE FRONT THROUGH TUE...GRADUALLY DIMINISHING AND TURNING MORE TO THE NE-E AS HIGH PRES SLIDES ACROSS THE CAROLINAS BY EARLY WED. MAINLY MODERATE NE-E WINDS AND 4-7 SEAS ARE EXPECTED LATE WED INTO THU. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 65W... MODEL PREFERENCE: PREVIOUS/OFFICIAL FORECAST BLENDED WITH LATEST GFS. NWPS/MWW3 BLEND USED FOR WAVE PARAMETERS. MEDIUM-HIGH CONFIDENCE. A GALE WARNING IS IN EFFECT FOR THE COAST OF COLOMBIA. THE WARNING IS CURRENTLY SET TO EXPIRE AFTER 12Z SUN MORNING. THE MODELS AGREE ON A SOLID AREA OF 30 KT WINDS HERE DURING THE EARLY MORNING DIURNAL MAXIMUM. ASCAT SCATTEROMETER PASSES THE PAST FEW MORNING HAVE ALL SHOWED 30-34 KT BARBS IN THIS AREA AND EXPECT THE SAME CONDITIONS SUN MORNING UNDER THE SAME SYNOPTIC PATTERN. OTHERWISE...HIGH PRESSURE N OF THE AREA WILL MAINTAIN FRESH TO STRONG TRADE WINDS ACROSS THE CARIBBEAN INTO MON...EXCEPT MODERATE TO FRESH IN THE NW CARIBBEAN WHERE THE PRESSURE GRADIENT WILL BE SLIGHTLY WEAKER. TRADE WINDS WILL DIMINISH SIGNIFICANTLY LATE MON INTO TUE AS THE PRESSURE GRADIENT N OF THE AREA WEAKENS DUE TO COLD FRONTAL INTRUSION. WINDS WILL BE LIGHT TO MODERATE BASIN WIDE TUE INTO WED...WITH SEAS DOWN TO 3-5 FT. THE GFS AND ECMWF HAVE COME INTO BETTER AGREEMENT ON THE TIMING AND STRENGTH OF THIS COLD FRONT...WITH THE FRONT SINKING S OF THE YUCATAN CHANNEL TUE NIGHT...GRADUALLY WASHING OVER THE NW CARIBBEAN THROUGH WED. THE GFS CONTINUES TO LOOK REASONABLE FOR THE FORECAST PACKAGE. IN THE TROPICAL N ATLC...FRESH TO LOCALLY STRONG TRADE WINDS WILL PREVAIL THROUGH THE WEEKEND...DIMINISHING OVER THE SOUTHERN WATERS SUN INTO MON S OF A SHEAR LINE DROPPING INTO THE AREA. SEAS WILL BE MAINLY 8-11 FT IN PRIMARILY NE SWELL. TUE INTO WED...WINDS WILL DIMINISH TO MODERATE TO FRESH ACROSS THE TROPICAL N ATLC WITH 7-9 FT SEAS AS A TROUGH MOVES FROM SE TO NW ACROSS THE WATERS. FOR THU...SEAS WILL STILL BE 6-9 FT IN NE-E SWELL EVEN THOUGH WINDS WILL HAVE DIMINISHED TO MAINLY MODERATE E-SE THROUGHOUT THE TROPICAL N ATLC BY THAT TIME. ...SW N ATLANTIC W OF 65W INCLUDING THE BAHAMAS... PREVIOUS/OFFICIAL FORECAST BLENDED WITH LATEST GFS. NWPS/MWW3 BLEND USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. THE BERMUDA HIGH CONTINUES TO DRIVE THE EASTERLY FLOW ACROSS THE AREA...WITH FRESH TO LOCALLY STRONG WINDS S OF 27N AND MODERATE TO LOCALLY FRESH N OF 27N. SEAS ARE GENERALLY 4-7 FT N OF 27N...AND 6-10 FT S OF 27N...EXCEPT 1-3 FT INSIDE THE BAHAMAS. TRADE WINDS WILL DIMINISH MON AFTERNOON AS THE NEXT COLD FRONT APPROACHES FROM THE W WEAKENING THE PRESSURE GRADIENT. THAT FRONT WILL MOVE INTO THE NW WATERS LATE MON. THE GFS AND ECMWF HAVE COME INTO BETTER AGREEMENT WITH THE TIMING AND STRENGTH OF THIS FRONT...REACHING FROM 31N75W TO S FLORIDA BY TUE MORNING AND FROM 31N65W TO NORTHERN CUBA NEAR 80W WED MORNING. THE GFS LOOKS REASONABLE FOR THE BASIS OF THIS FORECAST PACKAGE. FRESH TO STRONG NORTHERLY WINDS AND BUILDING SEAS WILL ARRIVE BEHIND THE FRONT TUE INTO WED...PERSISTING INTO THU AS THE FRONT EXTENDS FROM 26N65W TO THE SE BAHAMAS BY THU MORNING. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...GALE WARNING MON. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...GALE WARNING TODAY INTO SUN. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER LEWITSKY. NATIONAL HURRICANE CENTER.