000 AGXX40 KNHC 020755 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 355 AM EDT SAT MAY 2 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. MODEL PREFERENCE: 00 UTC GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. 00 UTC TAFB NWPS VALUES FOR WAVES FAVORING UKWAVE OVER THE SE GULF ON MON. HIGH CONFIDENCE. A WEAK COOL FRONT IS DRIFTING SOUTHWARD ACROSS THE EASTERN GULF THIS MORNING. BUOY OBSERVATIONS INDICATE THE AIRMASS BEHIND THE FRONT IS MODIFYING AND THE FRONT WILL LIKELY WASH THROUGH EARLY TODAY. 1019 MB HIGH PRES ANALYZED OVER THE NW GULF WILL BECOME ABSORBED INTO A LARGER HIGH PRES AREA CENTERED OVER THE TENNESSEE VALLEY. THIS WILL LEAVE A WEAK PRES PATTERN ACROSS THE GULF FOR THE REMAINDER OF TODAY INTO TONIGHT. THE HIGH PRES WILL BUILD AS IT SHIFT EASTWARD TONIGHT TOWARD THE CAROLINAS. THIS WILL BE IN PHASE WITH A WEAK SURFACE TROUGH EXTENDING FROM THE NW CARIBBEAN THROUGH WESTERN CUBA INTO THE FAR SE GULF. THE RESULTING TIGHT PRES GRADIENT WILL SUPPORT FRESH TO OCCASIONALLY STRONG E FLOW THROUGH THE STRAITS OF FLORIDA SUN THROUGH LATE MON. THE FETCH AND DURATION OF THE E FLOW AGAINST THE FLORIDA CURRENT WILL RESULT IN SEAS BUILDING TO 8 FT OVER THE SE GULF OFF THE NW COAST OF CUBA ON MONDAY. THIS IS BETTER REFLECTED IN UKWAVE OUTPUT AND THIS HAS BEEN INCORPORATED INTO THE OFFICIAL FORECAST. THE GRADIENT RELAXES BY TUE AS THE HIGH SHIFTS EAST AND TROUGHING TO THE SOUTH DAMPENS OUT...LEAVING GENERALLY MODERATE SE FLOW ACROSS MOST THE BASIN THROUGH MID WEEK WITH 4 TO 6 FT SEAS. WINDS WILL INCREASE TO 20 KT OVER THE NW GULF BY WED AHEAD OF LOW PRES FORMING OVER THE SOUTHERN PLAINS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 00Z GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. TAFB NWPS BLENDED WITH PREVIOUS FORECAST FOR SEAS. HIGH CONFIDENCE. A STATIONARY FRONT REACHES FROM EASTERN CUBA TO NE HONDURAS THIS MORNING. THE HIGHER SUN ANGLES OF EARLY MAY WILL ERASE THE DISTINCTION IN AIRMASSES ON EITHER SIDE OF THE FRONT ALLOWING IT TO BECOME DIFFUSE THROUGH LATE TODAY. AN APPROACHING UPPER TROUGH WILL SUPPORT A WEAK SURFACE TROUGH OVER THE NW CARIBBEAN AFTER THE FRONT WASHES OUT. MEANWHILE FARTHER EAST...THE SUBTROPICAL RIDGE IS SHIFTED A LITTLE MORE SOUTHEASTWARD DUE TO A SERIES OF STRONG UPPER IMPULSES NORTH OF THE AREA. THIS HAS BEEN KEEPING FRESH TO STRONG TRADE WINDS OFF THE EASTERN VENEZUELA COAST FOR THE PAST FEW DAYS. THIS PATTERN HAS STARTED TO TRANSITION IN RESPONSE TO STRONGER HIGH PRES CENTERED OVER THE EASTERN UNITED STATES. MODELS REMAIN IN GOOD AGREEMENT SHOWING THAT THIS WILL INCREASE TRADE WINDS AND DISPLACE THE MAIN AREA OF FRESH TO STRONG TRADES TO THE CENTRAL CARIBBEAN TO INCLUDE THE EASTERN COAST OF COLOMBIA THROUGH MID WEEK. WAVE HEIGHTS BUILD 8 TO 11 FT. MODERATE TO FRESH TRADES WILL PERSIST OVER THE TROPICAL N ATLC WITH SEAS 5 TO 7 FT. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: 00Z ECMWF BLENDED WITH PREVIOUS OFFICIAL. USED BLEND OF TAFB NWPS WITH PREVIOUS FOR SEAS. HIGH CONFIDENCE THROUGH MON...THEN MEDIUM CONFIDENCE THEREAFTER MOST PARTICULARLY WITH THE POSSIBLE FORMATION OF LOW PRES IN VICINITY OF BAHAMAS. A WEAK COOL FRONT REACHES FROM 31N71W TO THE NORTHERN BAHAMAS. THIS FRONT WILL WEAKEN AS IT DRIFTS SE THROUGH LATE TODAY...EVENTUALLY MERGING WITH A STATIONARY FRONT REACHING FROM 28N65W TO EASTERN CUBA THIS AFTERNOON. THE MERGED FRONT WILL THEN SHIFT SE BEFORE BECOMING DIFFUSE N OF HISPANIOLA AND PUERTO RICO SUNDAY. BUOY 41002 NEAR 32N75W IS SHOWING 25 KT WINDS FROM THE NW WITH SEAS TO 7 FT. THIS MOMENTUM WILL FOLLOW THE FRONT OVER THE WATERS N OF 30N BETWEEN 70W AND 77W THIS MORNING. WINDS WILL DIMINISH SLIGHTLY BY MIDDAY AS THE MAIN UPPER DYNAMICS LIFT OUT OF THE AREA...BUT LINGERING NW SWELL OF 8 TO 10 FT WILL PREVAIL ACROSS THE WATERS N OF 28N BETWEEN 68W AND 76W TONIGHT BEFORE SUBSIDING SUNDAY. HIGH PRES WILL BUILD OVER THE CAROLINAS SUNDAY AND MONDAY...MAINTAINING GENERALLY MODERATE TRADES OVER THE REGION EXCEPT FOR BRIEF PULSES OF STRONGER WINDS THROUGH THE SOUTHERN BAHAMAS AND OFF HISPANIOLA LATE SUNDAY AND LATE MONDAY. THE FORECAST ISSUE FOR TUESDAY AND WEDNESDAY CONTINUES TO BE THE DEVELOPMENT OVER LOW PRES OVER THE NORTHERN BAHAMAS. SOME SIGNIFICANT DISAGREEMENT CONTINUES IN MODEL OUTPUT REGARDING THE TIMING...POSITION AND STRENGTH OF THE LOW PRES. EARLIER RUNS OF THE UKMET WERE FAMILY AGGRESSIVE IN AGREEMENT WITH THE GFS...BUT RECENTLY THE UKMET HAS AGREED WITH THE MORE CONSERVATIVE ECMWF WHICH ITSELF HAS BACKED OFF SOMEWHAT. THE OFFICIAL FORECAST BLENDS THE MORE CONSERVATIVE ECMWF AND CALLS FOR A WEAKER LOW FORMING OVER THE NORTHERN BAHAMAS TUE NIGHT AND SHIFTING NE TO NEAR 31N75W BY WED NIGHT WITH WINDS IN EXCESS OF 25 KT ON THE NORTHERN PERIPHERY OF THE LOW AND SEAS BUILDING TO 8 FT N OF 28N BETWEEN 75W AND 78W. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 CHRISTENSEN. NATIONAL HURRICANE CENTER.