000 AGXX40 KNHC 081957 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 257 PM EST TUE DEC 8 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: 12 UTC GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. FOR WAVEHEIGHTS USED BLEND OF 12 UTC MWW3 WITH TAFB NWPS PARAMETERS INTO PREVIOUS OFFICIAL. HIGH CONFIDENCE. THE STATIONARY FRONT EARLIER THAT WAS ACROSS THE STRAITS OF FLORIDA HAS NUDGED SE TO A POSITION FROM NW CUBA TO A WEAK 1013 MB LOW IN THE FAR NW CARIBBEAN JUST S OF COZUMEL. HIGH PRESSURE IS BUILDING ACROSS THE GULF. LATEST BUOY OBSERVATIONS SHOW SEAS IN THE 2-3 FT RANGE N OF 26N...3-5 FT FROM 24N-26N AND 5-7 FT S OF 24N...EXCEPT FOR SLIGHTLY HIGHER SEAS OF 6-8 FT IN THE FAR SE PART OF THE GULF NEAR THE NW COAST OF CUBA. THE OBSERVATIONS INDICATE MODERATE TO FRESH NE TO E WINDS N OF 24N...EXCEPT FOR MODERATE SE WINDS N OF 26N W OF 93W. THE HIGH PRESSURE OVER THE AREA WILL SHIFT EASTWARD THROUGH FRI IN RESPONSE TO DEEPENING LOW PRES OVER THE CENTRAL UNITED STATES. SE FLOW WILL INCREASE SIGNIFICANTLY OVER THE FAR WESTERN GULF...TO THE FRESH RANGE...FRI INTO SUN WITH SEAS THERE BUILDING TO 6-8 FT. MODELS IN AGREEMENT THAT THE LOW PRES WILL PUSH THE NEXT COLD FRONT OF THE FALL SEASON INTO THE WESTERN GULF EARLY ON SUN. PRESENTLY...THE GUIDANCE INDICATES FRESH TO STRONG NLY FLOW BEHIND THE FRONT SUN WITH SEAS BUILDING TO THE RANGE OF 7-10 FT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 12 UTC GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. FOR WAVEHEIGHTS USED BLEND OF 12 UTC MWW3 WITH TAFB NWPS PARAMETERS INTO PREVIOUS OFFICIAL. HIGH CONFIDENCE. A STATIONARY FRONT EXTENDS FROM THE STRAITS OF FLORIDA SW ALONG THE NW COAST OF CUBA TO A 1013 MB LOW AT 20N87W. A TROUGH EXTENDS FROM THE LOW SE TO 16N85W. ATLC HIGH PRES N OF AREA CONTINUES TO SUPPORT FRESH TO STRONG WINDS ACROSS MUCH OF THE CENTRAL CARIBBEAN WITH SEAS IN THE RANGE OF 6-9 FT THERE. SEAS ELSEWHERE ARE IN THE RANGE OF 4-6 FT...EXCEPT FOR 2-4 FT BETWEEN THE FRONT AND 81W... AND 5-7 FT IN THE CENTRAL AND EASTERN TROPICAL N ATLC WATERS. NE WINDS OF 15 KT ARE NW OF THE FRONT ACROSS THE YUCATAN PENINSULA WITH SEAS OF 5-7 FT IN NE SWELL. THE HIGH PRES WILL SHIFT EASTWARD AND WEAKEN THROUGH THE FORECAST PERIOD. THE 1013 MB LOW WILL DRIFT SE THROUGH EARLY WED WHILE WEAKENING. THE TRADES IN THE CENTRAL CARIBBEAN SEAS WILL WEAKEN THU AS AN ATLC COLD FRONT PASSES TO THE N OF THE BASIN. THESE TRADES THEN MATERIALIZE AGAIN FRI NIGH INTO SAT WITH SEAS OF 8-9 FT... AND DIMINISH AGAIN ON SUN. THE 5-7 FT SEAS IN THE TROPICAL N ATLC SUBSIDE TO AROUND 5-6 FT ON FRI...AND CONTINUE INTO SUN. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: 12 UTC GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST...EXCEPT AN EVEN BLEND OF THE 12 GFS WITH THE 00 UTC ECMWF FOR WATERS NE OF THE BAHAMAS WED NIGHT THROUGH FRI. HIGH CONFIDENCE...EXCEPT MEDIUM CONFIDENCE NE OF THE BAHAMAS WED NIGHT THROUGH FRI. A COLD FRONT ENTERS THE BASIN FROM NEAR 31N69W SW TO THE NW BAHAMAS WHERE IT BECOMES A PERSISTENT STATIONARY FRONT SW TO THE STRAITS OF FLORIDA AND ALONG THE NW COAST OF CUBA TO A 1013 MB LOW IN THE NW CARIBBEAN JUST S OF COZUMEL. CLEARLY EVIDENT UPPER LEVEL DIFFLUENT FLOW OVER THE BAHAMAS AND STRAITS OF FLORIDA CONTINUES TO ENHANCE NUMEROUS SHOWERS AND TSTMS NOTED OVER MUCH OF THE BAHAMAS AND WATERS BETWEEN THE BAHAMAS CUBA...AND THE FLORIDA KEYS. CURRENT BUOY OBSERVATIONS AND LATEST ALTIMETER DATA SHOWS SEAS IN THE RANGE OF 6-7 FT N OF 28N BETWEEN 72W-78W...AND 4-6 FT S OF 28N EXCEPT FOR LOWER SEAS OF 1-2 FT IN WATERS WITHIN THE CENTRAL BAHAMAS. MAIN NEAR FUTURE UPCOMING CHANGES WILL BE RELATED TO LOW PRES THAT FORMS ALONG THE FRONT JUST TO THE NE OF THE BAHAMAS ON WED INDUCE BY SHORTWAVE ENERGY RIDING NEWD ALONG A VERY ACTIVE SW JET STREAM BRANCH THAT IS CURRENTLY HELPING TO FUEL THE AFOREMENTIONED SHOWER/TSTM ACTIVITY WITH THE STATIOANRY FRONT. THE ECMWF MODEL SOLN APPEARS TO REPRESENT THIS LOW FEATURE MORE CLEARLY THAN THE GFS IN THE BOUNDARY LAYER FIELDS. WITH THIS IN MIND...I BLENDED THE ECMWF WITH THE GFS IN THE NDFD GRIDS FOR WATERS NE OF THE BAHAMAS FOR PERIODS BEGINNING WED NIGHT INTO FRI. S-SW WINDS WILL INCREASE TO 20-25 KT OVER THE EASTERN PART OF ZONE 115 AND THE NORTHERN PART OF ZONE 121 ON WED WITH THESE WINDS SHIFTING TO THE EASTERN PART OF ZONE 115 BY LATE THU AFTERNOON AS THE LOW ACCELERATES TO NE OF THE FORECAST WATERS. SOME INCREASE OF E-SE WINDS IS ALSO EXPECTED IN THE EASTERN PART OF ZONE 113 WED NIGHT BEFORE SHIFTING INTO ZONE 115. SEAS ARE FORECAST TO BUILD TO 8 OR POSSIBLY 9 FT WITH THESE WINDS. CONDITIONS DIMINISH LATE THU NIGHT WITH THE LOW ACCELERATING AND ...MOVING FURTHER AWAY FROM THE AREA. THE ASSOCIATED COLD FRONT WILL REACH THE FAR SE WATERS BY FRI...AND WEAKEN TO A FRONTAL TROUGH THAT MOVES BACK TO THE W ACROSS THE SE BAHAMAS LATE FRI THROUGH LATE SAT. HIGH PRES WILL THEN SETTLE IN ACROSS THE BASIN THROUGH SUN NIGHT WITH AN INDUCED GRADIENT BETWEEN IT AND THE REMNANT FRONTAL TROUGH INCREASING NE WINDS TO MODERATE LEVELS BETWEEN THE SE BAHAMAS AND HAITI INCLUDING THE WINDWARD PASSAGE AND VICINITY WITH SEAS OF 5-7 FT...BUT MAY BE SLIGHTLY HIGHER. WILL ADJUST WAVEHEIGHT IN GRIDS AS ACCORDINGLY WITH RESPECT TO THESE WINDS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.