000 AGXX40 KNHC 230729 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 329 AM EDT SUN OCT 23 2016 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: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE. THE COLD FRONT THAT BROUGHT GALE CONDITIONS TO SOME SECTIONS OF THE FAR WRN GULF AND THE EXTREME SW GULF THE PAST 48 HRS...EXTENDS FROM W CNTRL CUBA SW TO 22N86W...THEN BECOMES STATIONARY TO JUST N OF THE YUCATAN PENINSULA AND TO THE ERN BAY OF CAMPECHE AS OF 06Z. A SURFACE TROUGH IS TO THE W OF THE STATIONARY FRONT FROM 20N94W WNW TO JUST S OF TAMPICO. HIGH PRES HAS BUILD ACROSS THE REGION BEHIND THE FRONT. THE ASSOCIATED ANTICYCLONIC FLOW IS NOTED IN THE CURRENT BUOY OBSERVATIONS...AND IN THE LATEST ASCAT DATA FROM LAST NIGHT. THESE OBSERVATIONS SHOW MODERATE N-NE WINDS E OF 90W...AND GENTLE TO MODERATE E-SE WINDS W OF 90W. THE EXCEPTION IS IN THE FAR SW GULF W OF THE FRONT AND S OF THE TROUGH WHERE AN ASCAT PASS FROM LAST NIGHT REVEALED STRONG NW WINDS BETWEEN THE TROUGH AND THE COAST OF MEXICO S TO NEAR 19N. THE OTHER EXCEPTION IS IN THE STRAITS OF FL WHERE A TIGHTER PRES GRADIENT IS PRODUCING FRESH NE WINDS THERE. THE CURRENT BUOY REPORTS AND LATEST ALTIMETER DATA SHOW SEAS IN THE RANGE OF 4-6 FT OVER MUCH THE GULF...EXCEPT FOR A SMALL POCKET OF 8-10 FT SEAS IN THE FAR SW GULF S OF 21N W OF 94W. SEAS OF 5-7 FT ARE IN THE STRAITS OF FL. THE LOWER SEA HEIGHTS...IN THE RANGE OF 1-2 FT...ARE CONFINED TO N OF A LINE FROM NE MX TO 28N94W TO 28N89W TO 29N84W TO 25N82W TO 23N82W. FOR THIS FORECAST PERIOD...THE WEATHER REGIME WILL CONTINUE TO BE DOMINATED BY HIGH PRES. THE CURRENT HIGH PRES IN PLACE WILL KEEP FRESH NE WINDS OVER THE SE GULF AND STRAITS OF FL THROUGH TUE MORNING AND GENTLE TO MODERATE ELY WINDS ELSEWHERE. STRONGER HIGH PRES WILL THEN BUILD SWD OVER THE WRN ATLC AND ERN GULF WATERS TUE AFTERNOON THROUGH THU NIGHT LEADING TO A TIGHTENING OF THE PRES GRADIENT OVER THE MUCH OF THE ERN GULF...WHICH IS EXPECTED TO LEAD TO FRESH TO LOCALLY STRONG NE-E WINDS OVER THOSE WATERS AND STRAITS OF FL. IN RESPONSE TO THIS INCREASE OF WINDS...SEAS ARE LIKELY TO BUILD TO AROUND 9 OR 10 FT IN THE FAR SE GULF AND STRAITS OF FL LATE WED THROUGH THU NIGHT AS THE WINDS OPPOSE COUNTER LOOP CURRENT FLOW CONDUCIVE FOR LARGE GROWTH OF SEAS. SEAS OF UP TO AROUND 7 FT IN E SWELL ARE EXPECTED TO SPREAD WWD TO THE ERN PORTIONS OF THE CNTRL GULF S OF ABOUT 26N THU AND THU NIGHT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE...EXCEPT AVERAGE CONFIDENCE TRPCL N ATLC WATERS AND ERN CARIBBEAN SEA TUE ONWARD. THE COLD FRONT THAT SWEPT ACROSS THE GULF OF MEXICO FRI THROUGH SAT EVENING EXTENDS FROM W CNTRL CUBA SW TO 22N86W AND STATIOANRY FROM THERE TO JUST N OF THE COAST OF THE YUCATAN PENINSULA AS OF 06Z. THE TAIL-END OF THE CNTRL ATLC TROUGH EXTENDS SW TO ERN CUBA. THE 06Z PRES ANALYSIS DEPICTS A RATHER WEAK PRES GRADIENT ACROSS JUST ABOUT THE ENTIRE CARIBBEAN...EXCEPT IN THE NRN YUCATAN CHANNEL WHERE MODERATE NE WINDS ARE PRESENT BEHIND THE FRONT. THE COLD FRONT IS FORECAST TO STALL FROM NEAR THE WINDWARD PASSAGE TO NE HONDURAS BY LATE THIS AFTERNOON OR EARLY EVENING...THEN BEGIN TO WEAKEN MON AND GRADUALLY DISSIPATE MON NIGHT THROUGH TUE NIGHT. MODERATE TO FRESH NE WINDS ARE EXPECTED NW OF THE FRONT. ONCE THE FRONT DISSIPATES...THE MODERATE TO FRESH WINDS NE BECOME MORE NE-E IN DIRECTION THROUGH THU OVER THE NW AND CNTRL CARIBBEAN...HOWEVER NE WINDS ARE FORECAST TO INCREASE TO FRESH TO LOCALLY STRONG IN THE LEE OF CUBA BEGINNING TONIGHT AND PULSE ON AND OFF THROUGH THE PERIOD AS A LARGE AREA OF STRONG HIGH PRES FROM THE U.S. ERN SEABOARD BUILDS SWD OVER THE WRN ATLC WATERS. SATELLITE IMAGERY CONTINUES TO SHOW QUITE AN IMPRESSIVE RATHER EXPANSIVE AREA OF CLOUDINESS AND DEEP CONVECTIVE ACTIVITY TO THE E OF THE TRPCL N ATLC WATERS. THIS IS DUE TO A LARGE AND SHARP UPPER LEVEL TROUGH THAT IS INTERACTING WITH DEEP TRPCL MOISTURE NEAR THE ITCZ. IN ADDITION...A TRPCL WAVE IS ANALYZED FROM NEAR 20N50W TO 11N53W AT 06Z MOVING W AT 10-15 KT. THE UPPER TROUGH WILL SLOWLY MOVE WWD THROUGH THE COUPLE OF DAYS...WHILE AT THE SAME TIME THE WAVE MOVES THROUGH THE TRPCL N ATLC WATERS. THE COMBINATION OF THESE FEATURES SHOULD PROVIDE AMPLE ATMOSPHERIC INSTABILITY...WHICH WILL SUPPORT INCREASING CHANCES FOR SCATTERED SHOWERS AND TSTMS ACROSS THAT PORTION OF THE ATLC...AND THEN TRANSITIONING WWD INTO SOME PORTIONS OF THE ERN CARIBBEAN SEA BY TUE NIGHT AND INTO WED BEFORE DIMINISHING SOME ON THU. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE. A COLD FRONT EXTENDS FROM NEAR 31N67W SW TO THE CNTRL BAHAMAS...AND TO W CNTRL CUBA AS OF 06Z. A SURFACE TROUGH EXTENDS FROM NEAR 31N66W SW TO THE SE BAHAMAS AND TO ERN CUBA ALSO OF 06Z. SCATTERED SHOWERS AND TSTMS ARE NOTED FROM 23N TO 26N BETWEEN 65W AND 67W. CURRENT BUOY OBSERVATIONS AND ASCAT DATA FROM LAST NIGHT SHOW GENERALLY GENTLE TO MODERATE NW WINDS BEHIND THE FRONT...WITH MAINLY GENTLE NW TO N WINDS S OF 25N W OF THE FRONT. THE 0152Z ASCAT PASS DEPICTED FRESH TO LOCALLY STRONG S-SW WINDS E OF THE TROUGH AND N OF 29N. THE OBSERVATIONS ALONG WITH RECENT ALTIMETER DATA REVEAL SEAS IN THE RANGE OF 4-6 FT N AND NE OF THE BAHAMAS...EXCEPT FOR HIGHER SEAS OF 6-9 FT N OF 29N E OF ABOUT 72W. LOWER SEAS OF 1-3 FT ARE SW OF THE BAHAMAS. THE COLD FRONT IS FORECAST TO REACH FROM NEAR 31N60W TO THE SE BAHAMAS AND TO ERN CUBA BY THIS EVENING...THEN BECOME STATIONARY FROM NEAR 25N65W TO NW HAITI AND WINDWARD PASSAGE MON THEN BEGIN TO WEAKEN MON AND SLOWLY DISSIPATE MON NIGHT THROUGH TUE NIGHT. THE PRES GRADIENT BETWEEN THE FRONT AND HIGH PRES IN ITS WAKE WILL ALLOW FOR GENTLE TO MODERATE NLY WINDS BEHIND THE FRONT ...EXCEPT FOR FRESH NE WINDS S OF 25N THROUGH MON NIGHT WITH SEAS OF 3-5 FT N OF 25N AND SEAS OF 5-8 FT S OF 25N. THE 6-9 FT SEAS N OF 29N E OF 72W WILL SUBSIDE TO 5-7 FT THIS AFTERNOON AND TO 4-5 FT ON TUE. BEGINNING TUE AFTERNOON...A LARGE AREA OF STRONGER HIGH PRES FROM THE U.S. ERN SEABOARD WILL BUILD SWD ACROSS JUST ABOUT THE ENTIRE BASIN AND EXPAND EWD THROUGH THU. MODELS IN VERY GOOD AGREEMENT THAT THE RESULTANT TIGHT PRES GRADIENT WILL BRING A SIGNIFICANT INCREASE OF NE-E WINDS...OF THE STRONG CATEGORY...TO ENCOMPASS THE BASIN ...WITH THE EXCLUSIONS OF THE FAR N AND SE PORTIONS. MODEL WAVE GUIDANCES SUGGEST SEAS BUILDING TO 10 FT E OF THE BAHAMAS BY WED EVENING IN A LARGE FETCH AREA...AND TO RANGE OF 8-12 FT ON THU. THIS WILL COULD PRODUCE HAZARDOUS MARINE CONDITIONS. E WINDS MAY ACTUALLY REACH NEAR 30 KT THROUGH THE STRAITS OF FL LATE ON THU WITH COMBINED SEAS AROUND 10 FT. .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS II COLLABORATION 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. $$ *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER AGUIRRE. NATIONAL HURRICANE CENTER.