000 AGXX40 KNHC 220749 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 249 AM EST SUN DEC 22 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. THE COLD FRONT MOVED INTO THE NW GULF LATE SAT AND NOW LIES FROM S CENTRAL LOUISIANA TO NE MEXICO. THE 0408 UTC ASCAT PASS SHOWS THE STRONG RETURN FLOW AHEAD OF THE COLD FRONT HAS SHIFTED SOUTHWARD INTO W CENTRAL GULF WATERS. THE FRONT IS FORECAST TO STALL HERE UNTIL SUN MORNING. A REINFORCING SURGE OF NORTHERLY WINDS AND COLD AIR ARRIVES IN THE NW PORTION LATE SUN INTO MON. THE 00Z GFS AND ECMWF CONTINUE TO 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 GFS HAS INCREASED THE PEAK WIND SPEED HERE TO 40 KT. GIVEN THE STRENGTH OF THIS COLD PUSH...THIS SEEMS REASONABLE. THE FORECAST GRIDS WILL BE ADJUSTED TO REFLECT THIS. THE 00Z GFS ALSO PUSHES GALE FORCE WINDS INTO GMZ025 TUE MORNING. THE 00Z GEFS SHOWS A 90 PERCENT CHANCE OF GALES IN ZONE GMZ023 MON AFTERNOON AND AS HIGH AS A 70 PERCENT CHANCE OF GALES IN ZONE GMX025 TUE MORNING. BOTH THE 00Z GEFS AND THE 21Z SREF 34 KT PROBABILITIES KEEP THE GALE AROUND UNTIL AT LEAST 12Z TUE...MORE LIKE THE OPERATIONAL GFS THAN THE ECMWF. THE GFS WILL BE USED TO ADJUST THE FORECAST. 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. HIGH CONFIDENCE. A GALE WARNING IS IN EFFECT FOR THE COAST OF COLOMBIA. THE WARNING IS CURRENTLY SET TO EXPIRE AFTER 12Z THIS 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 THIS MORNING UNDER THE SAME SYNOPTIC PATTERN. THE MODELS HAVE TRENDED TOWARD DIMINISHING THE WINDS HERE MORE RAPIDLY ON MON AND TUE. WHILE THE 00Z GFS CONTINUES TO CARRY A SOLID AREA OF 30 KT WINDS HERE MON MORNING...IT IS NOT AS LARGE AN AREA AS THE GFS RUN FROM THE SAME TIME YESTERDAY. THE ECMWF HAS BACKED OFF EVEN FURTHER WITH THE AREAL COVERAGE OF 30 KT WINDS. WILL CONTINUE TO ALLOW THE GALE WARNING TO EXPIRE LATER THIS MORNING BASED ON THIS WEAKENING MODEL TREND. 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 OVER THE AREA WEAKENS DUE TO COLD FRONTAL INTRUSION AND THE AMPLIFICATION OF A TROUGH MOVING INTO THE EASTERN CARIBBEAN. WINDS WILL BE LIGHT TO MODERATE BASIN WIDE TUE...WITH SEAS DOWN TO 3-6 FT. THE GFS BRINGS THE FRONT THROUGH THE YUCATAN CHANNEL EARLY TUE MORNING AND STALLS IT IN THE FAR NW GULF UNTIL IT RETROGRADES NORTHWARD WED AS TROUGHING BUILDS OVER THE NE CARIBBEAN. THE ECMWF AND UKMET ARE WEAKER WITH THE FRONT OVER THE NW CARIBBEAN THAN THE GFS ON TUE. GIVEN THE STRENGTH OF THE COLD AIR WITH THIS FRONT...WILL CONTINUE TO EDGE TOWARD THE GFS SOLUTION. IN THE TROPICAL N ATLC...FRESH TO LOCALLY STRONG TRADE WINDS CONTINUE IN THE REGION WITH SEAS WILL MAINLY 8-11 FT IN PRIMARILY NE SWELL. WINDS WILL DIMINISH OVER THE SOUTHERN WATERS LATE TODAY INTO MON AND SEAS WILL SUBSIDE TO 7-9 FT SEAS AS A TROUGH MOVES FROM SE TO NW ACROSS THE WATERS. THIS TROUGH WILL PASS UNDER A DEVELOPING UPPER LOW TUE AND WED THAT WILL AMPLIFY IT AT THE SURFACE AS IT MOVES INTO THE EASTERN CARIBBEAN. THIS WILL WEAKEN THE PRESSURE GRADIENT...WITH LIGHT TO MODERATE SOUTHEASTERLY WINDS EXPECTED N OF 15N TUE THROUGH THU. ...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. THE 0224 UTC ASCAT PASS SHOWS 25-30 KT WINDS IN THE APPROACHES TO THE WINDWARD PASSAGE. THE MODELS ARE RUNNING LOW HERE. ADJUSTMENTS WILL BE MADE TO THE FORECAST ACCORDINGLY. TRADE WINDS WILL BEGIN TO DIMINISH MON AFTERNOON AS THE NEXT COLD FRONT APPROACHES FROM THE W...WEAKENING THE PRESSURE GRADIENT. BOTH THE GFS AND ECMWF SHOW THAT FRONT MOVING INTO THE NW WATERS MON EVENING...REACHING FROM 31N75W TO HOBE SOUND FLORIDA BY TUE MORNING AND FROM 31N65W TO NORTHERN CUBA NEAR 80W WED MORNING. THE FRONT INTERACTS WITH THE AFOREMENTIONED AMPLIFYING TROUGHING OVER THE NE CARIBBEAN...LIMITING ITS SOUTHERN PROGRESS BY WED. THE TROUGHING WILL SHIFT W OVER THE EASTERN BAHAMAS BY THU...WEAKENING THE PRESSURE GRADIENT AND THE WINDS OVER SOUTHERN WATERS. THE GFS SOLUTION LOOKS REASONABLE HERE. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...GALE WARNING MON INTO MON NIGHT. GALE CONDITIONS POSSIBLE MON NIGHT INTO TUE. GMZ025...GALE CONDITIONS POSSIBLE MON NIGHT INTO TUE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...GALE WARNING EARLY TODAY INTO TODAY. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER SCHAUER. NATIONAL HURRICANE CENTER.