000 AGXX40 KNHC 150927 CCA MIMATS MARINE WEATHER DISCUSSION...CORRECTED NWS NATIONAL HURRICANE CENTER MIAMI FL 300 AM EST TUE DEC 15 2015 CORRECTED CARIBBEAN SEA AND TROPICAL N ATLC SECTION TO INCLUDE MENTION OF SWELL 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: FOR WINDS USED BLEND OF 00 UTC GFS WITH PREVIOUS OFFICIAL. FOR WAVEHEIGHTS USED 00 UTC MWW3/TAFB NWPS OUTPUT WITH PREVIOUS OFFICIAL...EXCEPT USED NWPS ONLY FOR SW GULF THU THROUGH FRI NIGHT. HIGH CONFIDENCE...EXCEPT MEDIUM CONFIDENCE SW GULF THU THROUGH FRI. THE COLD FRONT OF THE PREVIOUS DAYS HAS REACHED A POSITION FROM THE FLORIDA BIG BEND AREA SW TO 24N89W WHERE IT BECOMES A STATIONARY FRONT TO 22N94W...THEN DISSIPATING TO 19N95W. A FEW PATCHES OF RAIN WITH ISOLATED WEAK SHOWERS AND TSTMS ARE NOTED E OF THE FRONT OVER THE NE GULF. WEAK HIGH PRES IS PRESENT ELSEWHERE ACROSS THE GULF. THE BUOY OBSERVATIONS SHOW SEAS IN THE RANGE OF 3-5 FT W OF 83W...AND 2-3 FT E OF 83W. THE FRONT WILL CONTINUE WEAKEN AND STALL TODAY. IT WILL LIFT BACK N AS A WARM FRONT REACHING THE N CENTRAL GULF ZONE WED. MODELS IN PRETTY GOOD AGREEMENT THAT A STRONG COLD FRONT WILL EMERGE OFF THE TEXAS COAST WED MORNING...AND REACH FROM NEAR NEW ORLEANS TO TAMPICO WED NIGHT...FROM THE FLORIDA BIG BEND TO THE SW GULF THU NIGHT...AND PASS SE OF THE GULF FRI AFTERNOON. MAINLY FRESH TO STRONG N WINDS WITH QUICKLY BUILDING SEAS WILL FOLLOW IN THE WAKE OF THE FRONT...WITH THE POSSIBILITY OF WINDS TO GALE FORCE IN THE SW GULF THU NIGHT INTO FRI. THE NAM AND SREF MODEL GUIDANCES ...LIKE THE GLOBAL MODELS...AGREE ON DEPICTING AN IMPRESSIVE LARGE AREA OF FRESH TO STRONG NE WINDS ENCOMPASSING THE EASTERN FRI THROUGH SAT NIGHT RESULTING FROM A TIGHT PRES GRADIENT DUE TO STRONG HIGH PRES THAT WILL BE CENTERED OVER THE SOUTHERN U.S. THIS COULD LEAD VERY ROUGH CONDITIONS FOR MARINERS ACROSS THOSE WATERS DURING THOSE TIME PERIODS...ESPECIALLY FOR THOSE CROSSING THE WATERS OF THE YUCATAN CHANNEL AND STRAITS OF FLORIDA AREAS WHERE COUNTER CURRENT FLOW WILL BE MOST PROMINENT. NWPS WAVE PARAMETERS LOOK GOOD FOR THESE WINDS IN THE SW GULF. UPWARD ADJUSTMENTS WERE MADE TO WAVEHEIGHT GRIDS IN THE THU NIGHT THROUGH SAT PERIODS FOR THE SE GULF PORTION INCLUDING VICINITY OF YUCATAN CHANNEL. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...CORRECTED MODEL PREFERENCE: FOR WINDS USED BLEND OF 00 UTC GFS WITH PREVIOUS OFFICIAL. FOR WAVEHEIGHTS USED BLEND OF 00 UTC MWW3/TAFB NWPS OUTPUT WITH PREVIOUS OFFICIAL. HIGH CONFIDENCE...EXCEPT MEDIUM CONFIDENCE NW CARIBBEAN FRI NIGHT THROUGH SAT. AN UPPER LOW CENTERED OVER EASTERN CUBA CONTINUES TO SUPPORT SCATTERED SHOWERS AND TSTMS FROM THE WINDWARD PASSAGE SW TO WATERS BETWEEN JAMAICA AND HAITI...AND SW FROM THERE TO NEAR 13N BETWEEN 76W-79W. A 1020 MB ATLC HIGH CENTER IS ABOUT 130 NM S OF BERMUDA. THE PRES GRADIENT BETWEEN THIS HIGH AND LOW PRESSURE OVER NW COLOMBIA WEAKENED YESTERDAY ALLOWING FOR TRADES TO DECREASE TO MODERATE TO FRESH ACROSS THE CARIBBEAN BASIN. THE HIGH WILL CONTINUE TO DRIFT SE AND WEAKEN THROUGH WED ...WHICH WILL ALLOW FOR SIMILAR TRADE WINDS TO PERSIST ACROSS THE CARIBBEAN THRU WED NIGHT. ON THU...STRONG HIGH PRES WILL BUILD SE OVER THE CENTRAL ATLC AND WILL SUPPORT A STRENGTHENING PRES GRADIENT OVER THE CENTRAL CARIBBEAN WITH WINDS INCREASING TO FRESH TO STRONG BY THU NIGHT. SEAS WILL BUILD TO 8 TO 9 FT THU NIGHT THRU FRI NIGHT OVER THE S CENTRAL CARIBBEAN AS A RESULT OF THE STRONGER TRADES. A COLD FRONT WILL CROSS THE GULF OF MEXICO ON THU. THIS FRONT IS FORECAST TO ENTER THE NW CARIBBEAN ON FRI EVENING...AND REACH FROM CENTRAL CUBA TO THE GULF OF HONDURAS SAT MORNING. STRONG TO NEAR GALE FORCE WINDS WITH BUILDING SEAS ARE EXPECTED N OF THE FRONT. IN THE TROPICAL N ATLC...EXPECT LONG PERIOD N SWELL TO ARRIVE OVER THE FAR EASTERN PORTIONS WITH 8 FT SEAS. THE SWELL WILL GRADUALLY SPREAD WESTWARD TO NEAR 60W INTO SAT WITH RESULTANT SEAS OF 8-9 FT. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: FOR WINDS USED BLEND OF 00 UTC GFS WITH PREVIOUS OFFICIAL. FOR WAVEHEIGHTS USED BLEND OF 00 UTC MWW3/TAFB NWPS OUTPUT WITH PREVIOUS OFFICIAL. HIGH CONFIDENCE. THE PRES GRADIENT BETWEEN 1021 MB HIGH PRES ANALYZES ABOUT 130 NM S OF BERMUDA AND LOWER PRES ASSOCIATED WITH A COLD FRONT OVER THE NE GULF IS SUPPORTING FRESH S TO SW WINDS WITH SEAS OF 6-8 FT N OF 30N BETWEEN 74W-77W. AS BOTH THE HIGH AND FRONT CONTINUE TO WEAKEN... THE WINDS WILL DIMINISH TO 15-20 KT LATER THIS MORNING. THE LATEST SEA STATE ANALYSIS AND CURRENT BUOY OBSERVATIONS REVEAL SEAS IN THE 4-6 FT RANGE E OF THE BAHAMAS...EXCEPT FOR HIGHER SEAS OF 6-7 FT IN THE FAR SE PORTION AND 6-8 FT SEAS N OF 30N BETWEEN 74W-77W. THE LOWER SEAS OF 1-2 FT ARE LOCATED SW OF THE BAHAMAS. UPCOMING CHANGES FOR THE BASIN WILL BE SEEN AS FOLLOWS: THE AFOREMENTIONED GULF OF MEXICO COLD FRONT WILL MOVE FROM THE SE U.S. AND NE GULF TO JUST OFFSHORE THE NE FLORIDA AND GEORGIA COASTS THIS MORNING. WITH VERY LITTLE IN THE WAY OF UPPER SUPPORT ...THE FRONT WILL STALL ACROSS THIS SAME AREA DURING THIS AFTERNOON. THE FRONT WILL THEN TRANSITION TO A WARM FRONT...AND LIFT N OF THE AREA ON WED. A STRONGER COLD FRONT WILL APPROACH THE NW PORTION OF THE AREA ON THU WITH FRESH TO STRONG S TO SW WINDS DEVELOPING N OF THE BAHAMAS AHEAD OF THE FRONT. THIS INCREASE IN WINDS WILL SPREAD OUT AHEAD OF THE FRONT AS THE FRONT ENTERS THE NW PORTION OF ZONE 111 NEAR 12 UTC FRI. HIGH PRES BEHIND THE FRONT WILL SUPPORT FRESH TO STRONG NW TO N WINDS WITH THE FRONT REACHING A POSITION FROM NEAR 31N74W TO THE CENTRAL BAHAMAS AND TO WESTERN CUBA BY EARLY FRI EVENING...AND FROM NEAR 31N66W TO EASTERN CUBA BY SAT AFTERNOON. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... .GMZ023...SW GULF S OF 22N W OF 94W... GALE CONDITIONS POSSIBLE THU NIGHT INTO FRI. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.