000 AGXX40 KNHC 121932 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 232 PM EST SAT DEC 12 2015 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: OFFICIAL BLENDED WITH LATEST RUN OF GFS AND ECMWF. A SFC RIDGE AXIS EXTENDS FROM 1026 MB HIGH PRES NEAR 32N70W TO N FL TO THE W GULF NEAR 24N98W. DEVELOPING LOW PRESSURE OVER NEW MEXICO IS HELPING TO STRENGTHEN THE PRESSURE GRADIENT OVER THE W GULF WHICH IS SUPPORTING FRESH TO STRONG SE WINDS MAINLY N OF 26N W OF 90W. A 1306 UTC SCATTEROMETER PASS CONFIRMS WINDS TO 25 KT OVER THE NW GULF...WITH SEAS LIKELY BUILDING TO NEAR 8 FEET THIS AFTERNOON. WINDS ACROSS THE NW GULF WILL CONTINUE TO INCREASE SLIGHTLY THROUGH THE EVENING AND EXPAND S WITH FRESH TO STRONG SE WINDS ANYWHERE N OF 23N TO THE N GULF COAST W OF 90W THRU TONIGHT. IN THIS WIND REGIME...SEAS WILL BUILD AS HIGH AS 11 FT BY DAYBREAK SUNDAY. THE LOW OVER NEW MEXICO WILL TRACK E OVER N TX AND BRING A COLD FRONT TO THE TX GULF COAST LATE SUN AM...WITH THE FRONT MOVING SE OVER THE GULF EXTENDING FROM LOUISIANA TO VERA CRUZ BY SUN EVENING. MEANWHILE...THE HIGH OVER THE ATLC WILL SLIDE E AND WEAKEN THROUGH THE DAY SUN. THIS WILL ALLOW THE AREAL COVERAGE OF FRESH TO STRONG SE WINDS TO SHRINK TO WITHIN 60 NM OF THE COLD FRONT AS IT ENTERS THE CENTRAL GULF SUN PM. FRESH TO STRONG N WINDS ARE ALSO EXPECTED WITHIN 60 NM W FRONT. ON MONDAY NIGHT THE COLD FRONT BEGINS TO STALL OUT FROM SW TO NE OVER THE GULF WITH WINDS SUBSIDING BELOW 20 KT ACROSS THE ENTIRE BASIN. AS FOR CONVECTION...SHOWERS AND THUNDERSTORMS WILL BE LIKELY WITHIN 200 NM E OF THE COLD FRONT AS IT APPROACHES THE GULF COAST AND THROUGHOUT THE DAY SUN AS THE FRONT MOVES SE. AS THE FRONT BEGINS TO WEAKEN MON NIGHT THE COVERAGE OF CONVECTION IS FORECAST TO DECREASE. ON TUE...THE REMAINING STATIONARY PORTION OF THE FRONT OVER THE EASTERN GULF WILL CONTINUE TO BE THE FOCUS OF WEAK CONVECTION. BEYOND TUE...MODELS ARE IN GOOD AGREEMENT ON BRINING A STRONGER COLD FRONT OVER THE NW GULF WITH FRESH TO STRONG NORTHERLY WINDS STARTING IN THE NW GULF WED PM AND EXPANDING ACROSS THE THE MAJORITY OF THE GULF BY FRI. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: OFFICIAL BLENDED WITH LATEST RUN OF GFS AND ECMWF. SURFACE PRES GRADIENT DUE TO HIGH PRES CENTERED BETWEEN THE SE US AND BERMUDA...AND A 1008 MB LOW OVER THE SW CARIBBEAN CONTINUES TO SUPPORT FRESH TO STRONG TRADE WINDS OVER THE S CENTRAL CARIBBEAN. AN UPPER TROUGH AXIS EXTENDS FROM THE BAHAMAS SW TO HONDURAS...SUPPORTING SHOWERS AND ISOLATED THUNDERSTORMS FROM THE WINDWARD PASSAGE TO JAMAICA TO THE GULF OF HONDURAS. THE PRESSURE GRADIENT SUPPORTING THE STRONGER TRADES OVER THE S CENTRAL CARIBBEAN IS FORECAST TO REMAIN IN TACT THROUGH MIDDAY SUNDAY. SEAS OF 8 TO 10 FT WILL BE POSSIBLE IN THIS REGION THROUGH THAT TIME. THE HIGH THEN SLIDES E AND WEAKENS IN RESPONSE TO THE APPROACHING COLD FRONT OVER THE GULF OF MEXICO SUN PM. THE TRADE WINDS WILL THEN WEAKEN SLIGHTLY...BELOW 20 KT BASIN- WIDE BY SUNDAY EVENING. LINGERING SWELL OVER 8 FT WILL BE POSSIBLE OVER PORTIONS OF THE S CENTRAL CARIBBEAN THROUGH SUN NIGHT AFTER WINDS SUBSIDE. THE ATLC RIDGE AXIS WILL EXPAND W LATER THIS WEEK...WITH A POSSIBLE RETURN OF FRESH TO STRONG TRADES FOR THE S CENTRAL CARIBBEAN BY THU. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: OFFICIAL BLENDED WITH LATEST RUN OF GFS AND ECMWF. AN UPPER TROUGH OVER THE BAHAMAS SUPPORTS A SURFACE TROUGH FROM 26N72W TO 22N74W. A STATIONARY FRONT EXTENDS FROM A FRONTAL SYSTEM OVER THE CENTRAL ATLC TO 24N65W TO 23N69W. THESE FEATURES SUPPORT SCATTERED SHOWERS AND ISOLATED CONVECTION FROM THE CENTRAL AND SE BAHAMAS E THRU 64W. A 1026 MB HIGH IS CENTERED TO THE N NEAR 32N70W. THE PRES GRADIENT BETWEEN THE HIGH AND SURFACE TROUGH IS BEGINNING TO PRODUCE FRESH TO STRONG E TO NE WINDS FROM THE N BAHAMAS E TO 65W...AS CONFIRMED BY AN EARLIER SCATTEROMETER PASS. THESE WINDS WILL SUPPORT SEAS TO 9 FT THROUGH THE EVENING. THESE WINDS ARE FORECAST TO CONTINUE ACROSS THIS SAME AREA THROUGH THE EVENING AND WILL THEN GRADUALLY SHIFT TO THE NW AS THE SURFACE TROUGH DRIFTS NW AROUND THE PERIPHERY OF THE RIDGE. THIS GRADIENT AND ASSOCIATED WINDS AND SEAS WILL CONTINUE N...OFFSHORE THE FL COAST AND EVENTUALLY THE FL/GA COAST BY MON AM. BY MONDAY NIGHT A COLD FRONT WILL APPROACH THE NW ZONE AMZ111 WITH THE SURFACE TROUGH LIKELY MERGING INTO THE ONCOMING FRONTAL ZONE OVER THIS AREA. THE COLD FRONT WILL BE LIMITED IN ITS SOUTHWARD PROGRESS EARLY THIS WEEK DUE TO RIDGING TO THE S. HOWEVER...THE COLD FRONT WILL LIKELY MOVE W TO E...N OF 28N ACROSS THE W ATLC THROUGH THE FIRST HALF OF THE WEEK WITH CONVECTION. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 LATTO. NATIONAL HURRICANE CENTER.