000 AGXX40 KNHC 150754 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 254 AM EST MON DEC 15 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 FORECAST. USED BLEND OF 0000 UTC MWW3 WITH PREVIOUS OFFICIAL FOR FOR WAVE HEIGHTS. HIGH CONFIDENCE. LATEST BUOYS...OIL RIG PLATFORMS AND AVAILABLE PARTIAL ASCAT DATA ALONG WITH A FEW SHIP OBSERVATIONS SHOW GENTLE N-NE WINDS E OF 87W...WITH SLIGHTLY HIGHER WINDS S OF 24N E OF 87W. W OF 87W...THE OBSERVATIONS SHOW RETURN SE FLOW CONSISTING OF MODERATE INTENSITY WINDS. THE OBSERVATIONS FROM THE BUOYS REVEAL RELATIVELY LOW SEAS IN THE 1-3 FT RANGE...EXCEPT FOR POCKETS OF 3-4 FT SEAS WITHIN 150 NM EITHER SIDE OF A LINE FROM 22N86W TO 24N92W TO 28N97W. THE LATEST SYNOPTIC ANALYSIS HAS A 1021 MB HIGH PRES CENTER OVER THE TENNESSEE VALLEY WITH RIDGE EXTENDING SSE TO OVER THE MUCH OF THE GULF. THE RIDGE WILL SHIFT EASTWARD THROUGH TUE NIGHT WHILE WEAKENING...AND AS LOW PRES ADVANCES EASTWARD ACROSS THE PLAINS. MODERATE RETURN SLY FLOW OVER THE WESTERN WILL REMAIN IN PLACE THROUGH THIS MORNING...THEN WEAKEN THIS AFTERNOON AS THE COLD FRONT ASSOCIATED WITH THE LOW PRES MOVES ACROSS EASTERN TEXAS. THE COLD FRONT WILL MOVE OFF THE TEXAS AND SW LOUISIANA COASTS THIS EVENING....AND IS FORECAST TO REACH FROM NEAR MOBILE ALABAMA TO JUST N OF BROWNSVILLE TEXAS BY DAYBREAK TUE...AND FROM THE FLORIDA PANHANDLE TO JUST S OF BROWNSVILLE BY TUE EVENING...WHERE THE W PORTION WILL STALL. THE FRONT WILL THEN REACH FROM NEAR TAMPA FLORIDA TO NEAR 26N89W...STATIONARY TO 26N93W AND WARM FRONT TO FAR SOUTHERN TEXAS EARLY WED MORNING. THE WARM FRONT SEGMENT WILL LIFT NORTHWARD WED NIGHT THROUGH FRI NIGHT WHILE THE COLD FRONT AND STATIONARY PORTIONS BECOME DIFFUSE AS HIGH PRES BUILDS SE ACROSS THE EASTERN AND CENTRAL GULF. ANOTHER COLD FRONT IS FORECAST TO MOVE ACROSS EASTERN TEXAS FRI. LATEST ECMWF GUIDANCE APPEARS TOO AGGRESSIVE AND TOO FAST WITH THIS NEXT FRONT AS WELL TOO FAR S WITH THE PARENT LOW COMPARED WITH THE DETERMINISTIC AND PARALLEL GFS RUNS AND OTHER GLOBAL MODELS. FOR DAY 5 (FRI) WILL LEAN CLOSER TO THE SLOWER AND WEAKER GFS WHICH IS SIMILAR TO THE NAVGEM AND UKMET MODEL SOLNS. EXPECT SE RETURN FLOW TO INCREASE OVER THE FAR WESTERN GULF BEGINNING LATE WED...AND INTO LATE THU BEFORE THE DIMINISHING FRI WITH THE APPROACHING FRONT. SEAS THERE ARE EXPECTED TO PEAK UP TO 5 FT...POSSIBLY 6 TO 7 FT AT TIMES... LATE THU INTO FRI. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. USED BLEND OF 0000 UTC MWW3 WITH PREVIOUS OFFICIAL FOR FOR WAVE HEIGHTS. HIGH CONFIDENCE. LATEST SYNOPTIC ANALYSIS HAS A STRONG RIDGE EXTENDING SEWD ACROSS THE NW CARIBBEAN AND ALONG CENTRAL AMERICA. THE RESULTANT PRES GRADIENT IS BRINGING MODERATE TO FRESH NLY WINDS TO THE FAR WESTERN CARIBBEAN BETWEEN THE COASTS OF NICARAGUA AND SOUTHERN HONDURAS E TO 82W. THE DURATION OF THESE WINDS HAS ALLOWED SEAS TO BUILD TO AROUND 8 FT THERE. ELSEWHERE ACROSS THE CARIBBEAN...BUOY AND ASCAT DATA ARE SHOWING MAINLY GENTLE NE-E WINDS THROUGHOUT EXCEPT FOR GENTLE E-SE WINDS E OF 69W WITH A SMALL AREA OF GENTLE SE-S WINDS N OF 14N E OF 68W. SEAS ELSEWHERE IN THE CARIBBEAN ARE IN THE 4-6 FT RANGE...EXCEPT FOR LOWER SEAS OF 3-4 FT E OF 69W...AND 2-3 FT IN NE CARIBBEAN. SEAS IN THE TROPICAL N ATLC HAVE SUBSIDED TO 5-6 FT IN NE SWELLS WITH SMALL POCKETS OF 6-7 FT SEAS. SEAS WILL REMAIN IN THE RANGE OF 5-6 FT DURING THE PERIOD. THE MODERATE TO FRESH NLY WINDS OVER THE FAR WESTERN CARIBBEAN ARE FORECAST TO DIMINISH TO 15-20 KT TONIGHT AS THE PRES GRADIENT BETWEEN STRONG RIDGING OVER THE NW CARIBBEAN AND LOW PRES OVER THE SW CARIBBEAN SEAS SLACKENS. ...SW N ATLANTIC S OF 31N W OF 55W INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. USED NWPS/PREVIOUS OFFICIAL BLEND WITH 0000 UTC MWW3 FOR WAVE HEIGHTS. HIGH CONFIDENCE. THE PRELIMINARY 0600 UTC ANALYSIS SHOWS A WEAKENING COLD FRONT OVER THE FAR SE WATERS AS HIGH PRES BUILDS EASTWARD OVER THE REMAINDER OF THE BASIN. LATEST SATELLITE IMAGERY REVEALS AMPLE CLOUDINESS MAINLY AT THE MID AND UPPER LEVELS TO THE E AND SE OF THE FRONT WITH SCATTERED SHOWERS AND ISOLATED TSTMS. BOTH BUOYS AND A FEW SHIP OBSERVATIONS SHOW SEAS IN THE RANGE OF 5-7 FT E OF THE BAHAMAS DUE TO SUBSIDING N AND NE SWELLS. LOWER SEAS OF 3-4 FT ARE NW OF THE BAHAMAS...AND SW OF THE BAHAMAS WHERE SEAS ARE 1-3 FT. THE BUOYS ALONG WITH SEVERAL RECENT ASCAT PASSES ARE NOTING...AND RECENTLY REVEALED GENTLE SE-S WINDS TO THE SE OF THE PRE-FRONTAL TROUGH AND FRONT AND GENTLE NLY WINDS BEHIND THE FRONT WITH THE EXCEPTION OF MODERATE NW FLOW N OF 28N E OF 68W WHERE SEAS ARE IN THE 6-8 FT RANGE. THE AFOREMENTIONED WEAKENING COLD FRONT WILL TRANSITION TO A DISSIPATING STATIONARY FRONT THROUGH TUE...AND TO A REMNANT TROUGH LATE TUE AND WED. MODEL GUIDANCE IS IN GOOD AGREEMENT THAT NLY WINDS BEHIND THE FRONT WILL BE IN THE GENTLE RANGE WITH MODERATE NE WINDS EXPECTED PERIODICALLY BETWEEN THE SE BAHAMAS AND HISPANIOLA THROUGH FRI. SEAS E OF THE BAHAMAS WILL GRADUALLY LOWER TO 3-5 FT BY WED...AND REMAIN AT THAT RANGE THROUGH FRI. THE HIGH PRES CURRENTLY BUILDING OVER THE BASIN WILL CONTINUE TO DO SO THROUGH THU...BUT WEAKEN WITH THE PASSAGE OF ANOTHER COLD FRONT. THIS NEXT COLD FRONT IS EXPECTED TO MOVE INTO THE FAR NW CORNER OF THE BASIN TUE NIGHT FOLLOWED BY NW WINDS OF 15-20 KT...AND PRECEDED BY A SMALL AREA OF SW 15-20 KT WINDS WITH SEAS OF ABOUT 4-6 FT. THESE WINDS WILL THEN QUICKLY DIMINISH WED THROUGH FRI AS THE FRONT SWEEPS SEWD ACROSS THE FORECAST WATERS WHILE WEAKENING WITH WINDS ON EITHER SIDE OF IT DIMINISHING AND SEAS LOWERING TO 2-4 FT THROUGHOUT...EXCEPT FOR SLIGHTLY HIGHER SEAS OF 3-5 FT IN THE FAR SE WATERS AND 1-2 FT SEAS SW OF THE BAHAMAS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 AGUIRRE. NATIONAL HURRICANE CENTER.