000 AGXX40 KNHC 161827 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 127 PM EST TUE DEC 16 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: 12Z GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. 12Z TAFB-NWPS USED FOR WAVE HEIGHTS. HIGH CONFIDENCE. CURRENT SYNOPTIC ANALYSIS ALONG WITH SATELLITE AND RADAR DATA SHOWS A COLD FRONT EXTENDING FROM THE FLORIDA PANHANDLE NEAR 30N87W TO THE TEXAS COAST NEAR BROWNSVILLE. A 1022 HIGH PRES IS CENTERED ACROSS CENTRAL FLORIDA WITH A RIDGE AXIS EXTENDING SW TO NEAR 25N90W. LATEST SHIP OBS...BUOYS...OFFSHORE OIL PLATFORMS AND SCATTEROMETER DATA INDICATE GENTLE EASTERLY WINDS S OF 26N... GENTLE TO MODERATE SW WINDS WITHIN 120 NM E OF THE FRONT AND MODERATE TO FRESH N-NE WINDS W OF THE FRONT. CURRENT BUOY OBSERVATIONS ALONG WITH ALTIMETER DATA REVEAL RELATIVELY LOW SEAS IN THE 1-3 FT RANGE S AND E OF THE FRONT...AND SEAS OF 4-6 FT W OF THE FRONT. THE RIDGE WILL SHIFT EASTWARD AND WEAKEN THROUGH WED IN ADVANCE OF THE COLD FRONT NOW MOVING ACROSS THE NW AND NORTH-CENTRAL GULF. BY WED...THE COLD FRONT WILL REACH FROM VENICE FLORIDA TO 25N88W THEN STATIONARY TO 25N92W AND AS A WARM FRONT TO THE TEXAS COAST NEAR CORPUS CHRISTI. THE WARM FRONT SEGMENT WILL LIFT NORTHWARD WED NIGHT THROUGH THU NIGHT WHILE THE COLD FRONT AND STATIONARY PORTIONS BECOME DIFFUSE AS STRONGER HIGH PRES BUILDS SE ACROSS THE EASTERN AND CENTRAL GULF. RATHER WEAK HIGH PRES BEHIND THE FRONT WILL KEEP NORTHERLY WINDS IN THE GENTLE TO MODERATE RANGE WITH SEAS GENERALLY LESS THAN 6 FT THROUGH THU. ANOTHER COLD FRONT IS FORECAST TO EMERGE INTO THE WESTERN GULF FRI LATE...AND QUICKLY REACH FROM THE FLORIDA PANHANDLE TO THE SW GULF BY SAT LATE. WITH RESPECT TO CYCLOGENESIS...GLOBAL MODELS ARE ALL IN FAIRLY DECENT AGREEMENT THROUGH FRI LATE WITH A WEAK LOW DEVELOPING ALONG THE TEXAS GULF COAST AND INITIALLY MOVING ENE THROUGH SAT. BY SAT... MODELS BEGIN TO DIVERGE SLIGHTLY WITH THE POSITION OF THE LOW AND SUBSEQUENTLY THE POSITION/TIMING OF THE FRONT EXTENDING SSW ACROSS THE GULF WATERS. THE GFS AND ITS MEAN DEPICTS A BROAD AREA OF LOW PRESSURE ACROSS SOUTHERN MISSISSIPPI AND ALABAMA...WHILE THE ECMWF SHOWS A LOW POSITION IN THE VICINITY OF MOBILE BAY. BOTH GFS AND ITS MEAN ENSEMBLES ARE A BIT SLOWER AND WEAKER WITH THE WIND FIELD LATE FRI THROUGH SAT. THE ECMWF CONTINUES TO BE SLIGHTLY MORE ROBUST IN DEVELOPMENT AND AS A RESULT WINDS ARE SLIGHTLY STRONGER AROUND THE LOW. EXPECT GENTLE TO MODERATE SE RETURN FLOW TO INCREASE TO MODERATE TO OCCASIONALLY FRESH ACROSS THE FAR WESTERN GULF BEGINNING LATE WED...AND INTO LATE THU BEFORE DIMINISHING SLIGHTLY ON FRI WITH THE APPROACH OF THE FRONT. SEAS THERE ARE EXPECTED TO PEAK UP TO 6 FT ACROSS PORTIONS OF THE WESTERN GULF NEAR THE TEXAS COAST LATE FRI AND SAT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 12Z GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. 12Z TAFB-NWPS USED FOR WAVE HEIGHTS. HIGH CONFIDENCE. 12Z SYNOPTIC ANALYSIS SHOWS A STATIONARY FRONT ANALYZED ALONG 18N BETWEEN THE LEEWARD ISLANDS AND HISPANIOLA...WITH A SHEAR LINE CURVED FROM HISPANIOLA THROUGH 17N79W TO OFF THE COAST OF NICARAGUA NEAR 11N82W. GIVEN THE INDUCED STRONGER PRESSURE GRADIENT ACROSS THE NW CARIBBEAN...LATEST SCATTEROMETER DATA SHOWS FRESH TO OCCASIONALLY STRONG NE WINDS IN THE VICINITY OF THE WINDWARD PASSAGE AND AREAS SOUTH OF CUBA TO 17N. A NARROW CORRIDOR OF MODERATE NORTHERLY WINDS ARE FOUND TO THE WEST OF THE SHEAR LINE TO THE NICARAGUA COAST. SEAS REMAIN IN THE 3-6 FT RANGE ACROSS THE NW CARIBBEAN ARE EXPECTED TO SUBSIDE BY THU AS THE GRADIENT RELAXES. ELSEWHERE ACROSS THE CARIBBEAN...BUOY AND ASCAT DATA SHOW MAINLY GENTLE AND OCCASIONAL MODERATE NE-E WINDS THROUGHOUT EXCEPT FOR GENTLE ESE WINDS OVER THE FAR NORTHERN TROPICAL N ATLC WHERE A WEAKENING STATIONARY FRONT EXTENDS FROM 21N55W SW TO 18N63W. SEAS ELSEWHERE IN THE CARIBBEAN ARE IN THE 3-5 FT RANGE...EXCEPT FOR LOWER SEAS OF 2-3 FT IN THE FAR NW AND FAR NE CARIBBEAN SECTIONS. SEAS IN THE TROPICAL N ATLC ARE IN THE 5-6 FT RANGE PER CURRENT BUOY DATA AND RECENT ALTIMETER DATA. THESE SEAS WILL REMAIN IN THAT SIMILAR RANGE DURING THE PERIOD. ...SW N ATLANTIC S OF 31N W OF 55W INCLUDING THE BAHAMAS... MODEL PREFERENCE: 12Z GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. 12Z TAFB-NWPS USED FOR WAVE HEIGHTS. HIGH CONFIDENCE. 12Z ANALYSIS SHOWS A WEAKENING STATIONARY FRONT OVER THE FAR SE WATERS AS HIGH PRES BUILDS EASTWARD OVER THE REMAINDER OF THE BASIN. BOTH BUOYS AND A FEW SHIP OBSERVATIONS SHOW SEAS IN THE RANGE OF 4-6 FT E OF THE BAHAMAS...AND LOWER SEAS OF 2-3 FT ARE SEEN ELSEWHERE. RECENT ASCAT PASSES ARE NOTING LIGHT TO GENTLE WINDS N OF 20N AS THE HIGH AND ASSOCIATED RIDGING INFLUENCES MUCH OF THE AREA. THE AFOREMENTIONED WEAKENING STATIONARY FRONT WILL TRANSITION TO A REMNANT TROUGH TONIGHT INTO WED. WW3 AND NWPS MODEL GUIDANCE SHOWS THAT SEAS E OF THE BAHAMAS WILL CHANGE LITTLE THROUGH SAT NIGHT. THE HIGH PRES CURRENTLY BUILDING ACROSS THE AREA 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 TONIGHT INTO WED 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 SOUTHEASTWARD 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. HIGH PRES WILL ONCE AGAIN BUILD ACROSS THE BASIN IN THE WAKE OF THIS NEXT FRONT INTO SAT NIGHT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 HUFFMAN. NATIONAL HURRICANE CENTER.