000 AGXX40 KNHC 170630 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 130 AM EST TUE NOV 17 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: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. NWPS AND ECMWF USED FOR WAVES WITH MANUAL ADJUSTMENTS FOR OBSERVATIONS. MEDIUM CONFIDENCE. RESIDUAL CLOUDS AND SHOWERS WILL CONTINUE ACROSS EXTREME SE GULF EARLY TODAY. AN NE-SW ORIENTATED RIDGE DISSECTS THE GULF FROM THE FL BIG BEND TO E-CENTRAL MEXICO. SE RETURN FLOW AT 20-25 KT IS EXPECTED TO THE N OF 25N W OF 94W...WITH E-SE 15-20 KT FLOW ELSEWHERE. THE 20-25 KT CONDITIONS WILL GRADUALLY CLOCK TO SE-S WITH THE AFFECTED AREA SHIFTING NE ACROSS THE GULF WATERS N OF 26N W OF 92W EARLY THIS MORNING AHEAD OF A COLD FRONT MOVING OFF THE TX COAST DURING THE LATE MORNING HOURS. THE FRONT WILL REACH FROM THE MS DELTA TO THE E-CENTRAL MEXICAN COAST TONIGHT WITH SE- S 20-25 KT FLOW ACROSS THE GULF WATERS N OF 26.5N E OF THE FRONT. GUIDANCE HAS CHANGED CONSIDERABLY OVER THE PAST FEW RUNS AND NOW SLOWS THE FRONTAL ADVANCE TO A POSITION FROM THE EXTREME WESTERN FL PANHANDLE TO THE CENTRAL BAY OF CAMPECHE ON WED AFTERNOON. THE POST-FRONTAL FLOW IS NOW EXPECTED TO MAX AT ONLY 25 KT ALONG THE MEXICAN COAST NEAR 23N97W LATE WED MORNING AND THEN SHIFT SE TO NEAR 19N96W ON WED AFTERNOON...WITH WITH MODERATE NORTHERLY FLOW EXPECTED ELSEWHERE W OF THE FRONTAL BOUNDARY. THE N SEGMENT OF THE FRONT WILL MOVE E OF THE AREA OVER FL ON THU NIGHT WHILE THE PORTION S OF 27N STALLS ACROSS THE SE GULF. REMNANTS OF THE FRONT WILL DRIFT W ACROSS THE SE GULF ON SAT INTO EARLY SUN. REINFORCING HIGH PRES IN THE FORM OF FRESH NE FLOW WILL PUSH THE REMNANTS SE AGAIN ON SUN NIGHT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. NWPS AND ECMWF USED FOR WAVES WITH MANUAL ADJUSTMENTS FOR OBSERVATIONS. MEDIUM CONFIDENCE. ATLC HIGH PRESSURE N OF THE AREA IS SUPPORTING FRESH TO LOCALLY STRONG TRADES ACROSS THE S CENTRAL CARIBBEAN WITH SEAS TO 9 FT. THE GRADIENT WILL CONTINUE TO GRADUALLY RELAX TONIGHT THROUGH WED NIGHT. A MID LEVEL TROUGH EXTENDS S ACROSS THE NW CARIBBEAN INTO AN UPPER CYCLONE NEAR 12N78W WITH DIFFLUENCE OVER THE E SEMICIRCLE OF THE CYCLONE SUPPORTING LARGE TSTM CLUSTERS. ALL GUIDANCE SUGGEST A SURFACE LOW WILL DEVELOP OVER THE SW CARIBBEAN TODAY WITH THE GFS AND NAM STILL MORE AGGRESSIVE THAN THE ARRAY OF OTHER GUIDANCE. EXPECT THE LOW TO MEANDER OVER THE SW CARIBBEAN WATERS THROUGH EARLY FRI WITH FRESH NE-E FLOW WITHIN 300 NM N OF THE LOW WHICH SHOULD MOVE W AND INLAND COSTA RICA ON FRI. NOTE THAT RECENT GUIDANCE MOVES THE LOW INLAND A FULL 24 HOURS FASTER THAN YESTERDAYS GUIDANCE AND PROVIDES MUCH LESS OPPORTUNITY FOR DEVELOPMENT IN THE CARIBBEAN. LONG PERIOD N NE SWELL WILL PROPAGATE INTO THE TROPICAL WATERS E OF THE LEEWARDS ON FRI NIGHT THROUGH SUN. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL. LATEST NWPS FOR WAVES WITH MANUAL ADJUSTMENTS FOR OBSERVATIONS.. MEDIUM CONFIDENCE. A BROAD STATIONARY FRONT CURRENTLY EXTENDS E-W ALONG 25N ACCOMPANIED BY WIDESPREAD SHOWERS AND EMBEDDED ISOLATED TSTMS MAINLY ACROSS THE CENTRAL AND NW BAHAMAS. FRESH E WINDS ARE FORECAST BOTH N AND S OF THE FRONTAL TROUGH. REMNANTS OF THE STATIONARY FRONT WILL LIFT N AS A WEAK WARM FRONT BEGINNING TONIGHT WITH SE RETURN FLOW INCREASING TO 20-25 KT ACROSS THE WATERS NE OF THE WARM FRONT...ROUGHLY TO THE N OF 25N W OF 67W. THE STRONG WINDS WILL SHIFT N OF 31N LATE WED NIGHT AS A COLD FRONT MOVES OFF THE NE FL COAST REACHING FROM 31N74W TO THE NW BAHAMAS ON FRI...FROM 31N71W TO THE NW EARLY SAT...AND FROM 31N63W TO THE NW BAHAMAS ON SUN. MODERATE NLY FLOW W OF THE FRONT WILL INCREASE BRIEFLY TO FRESH ON FRI NIGHT N OF THE BAHAMAS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 NELSON. NATIONAL HURRICANE CENTER.