000 AGXX40 KNHC 130836 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 436 AM EDT SAT OCT 13 2012 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLC...AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... 1023 MB HIGH CENTERED ALONG THE AL-NW FL COASTS THIS MORNING MAINTAINING MODERATE ANTICYCLONIC FLOW ACROSS THE BASIN...EXCEPT FOR STRONGER WIND SE PORTIONS. 1030 MB HIGH ACROSS THE GREAT LAKES REGION AND ASSOCIATED REINFORCING SURGE OF NNE FLOW SPILLING INTO OFFSHORE ATLC WATERS THEN ACCELERATING SW ACROSS THE BAHAMAS..S FLORIDA...AND INTO SE GULF AND NW CARIB. 0228 UTC ASCAT PASS SHOWED NE WINDS 20 KT EXITING SW COAST OF FLORIDA AND MOVING SW ACROSS EXTREME SE GULF AND WRN CUBA...WITH ISOLATED SPOTS 25 KT AND 25-30 KT ACROSS THE WARM WATERS IN THE YUCATAN CHANNEL. UNFORTUNATELY...I HAVE NOT SHIP OBS REPORTING SEAS ACROSS THIS AREA OF RECENT...NOR ALTIMETER PASSES. GLOBAL MODELS FORECASTING SEAS 6-7 FT ACROSS THIS AREA WITH ISOLATED AREAS OF 8 FT...AND CROSS CHECK WITH WAVE NOMOGRAMS AT 20-24 KT WILL ONLY PRODUCE 9 FT AFTER BY 18 HRS. RTOFS DEPICTION OF YUCATAN CURRENT SHOWS IT EXITING THE CHANNEL AND FLOWING NE THEN NNE BETWEEN 84W AND 85W...AND IN DIRECT OPPOSITION TO WIND. IT IS HERE THAT SEAS ARE LIKELY IN EXCESS OF 10 FT AND COULD REACH AS HIGH AS 14-15 FT BY LATE MORNING. OTHERWISE...WINDS AND SEAS IN NORMAL RANGES ACROSS THE BASIN...WITH LONG ELY FETCH ACROSS SRN GULF FROM OFFSHORE OF YUCATAN WWD YIELDING SEAS 5-6 FT JUST N OF BUOY 42055. A SIGNIFICANT RELAXING OF THE GRADIENT ACROSS THE SE GULF IS EXPECTED EITHER LATE THIS AFTERNOON OR TONIGHT AS THE REMNANTS OF PATTY MOVE SW INTO THE CARIB. STLT IMAGERY ATTM FINALLY SHOWING PATTY LOSING ALL CNVTN AND BECOMING ELONGATED AND SHOULD CONTINUE SW AS FORECAST. ATTM AM LEANING TOWARD THE ECMWF SOLUTION WHICH WILL HANG ON TO STRONGER WINDS ACROSS SE GULF THROUGH THIS EVENING BEFORE DIMINISHING TONIGHT. SW N ATLC S OF 31N W OF 65W... ELONGATED LLVL TROUGHING AND MOSTLY MERGED FRONTAL ZONE CONTINUE THIS MORNING DIAGONALLY ACROSS THE AREA...FROM ERN CUBA NE TO NEAR 30N66W. AS MENTIONED ABOVE...SHEAR AND STRETCHING FINALLY FINISHING OFF PATTY ATTM...AND SHOULD SHIFT SW ACROSS THE S CENTRAL BAHAMAS LATER TODAY AND THEN INTO CUBA SUN. STRONG GRADIENT TO THE W AND NW OF PATTY AND FRONTAL ZONE ARE YIELDING NNE TO NE WINDS 20-25 KT ACROSS MUCH OF THE WATERS TO THE W OF THE FRONT...AND 25-30 KT WITHIN 60 NM OF THE FRONTAL ZONE PER AN 0227 UTC ASCAT PASS. WINDS LIKELY ACCELERATING THROUGH PASSAGES OF CENTRAL AND NW BAHAMAS...AND ACROSS WARM WATERS OF THE FLORIDA CURRENT...WITH A FEW SHIP OBS 30-35 KT NW BAHAMAS PAST FEW HOURS. THUS SEAS ARE VERY UNDERDONE BY MODELS AND WILL HAVE TO BE ADJUSTED UP TO 6-8 FT. THIS LONG NELY FETCH IS ALSO PRODUCING A BROAD ZONE OF 8-10 FT SEAS WITH AREAS OF 11-12 FT IN BANDS OF HIGHER WINDS. THIS WAVE ACTION SLAMMING INTO ATLC COASTS OF NW AND CENTRAL BAHAMAS AND EXPECTED TO PEAK THIS AFTERNOON AND EVENING AS MAX GRADIENT ASSOCIATED WITH PATTY REMNANTS MOVES BY. T.S. RAFAEL WILL THAN BEGIN TO LIFT OUT OF THE CARIB SUN AND MON AND SHIFT THE OLD FRONTAL ZONE N AND NW AND WITH IT THE AREA FRESH WINDS ALONG THE BOUNDARY. GRADIENT TO RELAX SUN AFTERNOON AND NIGHT AS WINDS VEER NE THEN E. AS FOR RAFAEL...BROAD ZONE OF 20-25 KT WINDS ACROSS THE N PORTIONS OF THE TROPICAL WAVE THAT THE STORM HAS DEVELOPED FROM ARE SPREADING NW ACROSS THE ATLC WATERS N AND NE OF THE LESSER ANTILLES...WITH BUILDING SEAS ACROSS ATLC E OF 68W THIS MORNING. BUOY 41043 N OF STT NOW AT 8 FT AND SHOULD GRADUALLY INCREASE NEXT 36 HRS AS RAFAEL LIFTS NNW OUT OF CARIB AND WIND FIELD BEGINS TO WRAP AROUND CORE CIRCULATION. STRONG SHEAR IS PREVENTING SIGNIFICANT DEVELOPMENT OF RAFAEL PRESENTLY BUT MAY RELAX ENOUGH FOR SOME STRENGTHENING BY 24 HOURS. AT ANY RATE...WINDS AND SEAS WILL BE ON THE INCREASE ACROSS SE PORTIONS NEXT 36 HOURS AND COULD PERSIST DEPENDING ON SPEED AT WHICH RAFAEL EXITS THE REGION TO THE N MON-TUE. LATEST NHC FORECAST TO SLOW FORWARD MOTION SUN AND MON AND REFLECT SLOWER MOTION IN RECENT MODEL RUNS. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... RAFAEL STILL BEGIN STRONGLY SHEARED ACROSS THE NE CARIB...WITH VAST MAJORITY OF WINDS AND WEATHER ACROSS THE BROAD E SEMICIRCLE OF THIS LARGE CIRCULATION. FOR THE ISLANDS...RAINFALL WILL LIKELY BE THE STRONGEST IMPACT FROM RAFAEL...AS IT PULLS THE ITCZ AND ABUNDANT TROPICAL MOISTURE WITH IT. THESE SCENARIOS ARE CAPABLE OF YIELDING RAINFALL TOTALS IN EXCESS OF 20 INCHES. EXCEPT FOR WINDS IN SQUALLS ACROSS THE E AND SE SEMICIRCLE OF RAFAEL...AND INSIDE THE CARIBBEAN...STRONGEST WINDS AND HIGHEST SEAS ARE WELL REMOVED FROM THE CENTER AND ACROSS THE TROPICAL N ATLC WATERS...AND JUST TO THE N...WHERE BUOY 41044 HAS BEEN FLUCTUATING AT 10-11 FT...AND 12 FT SEAS LIKELY TO ITS SW. AGAIN...BROAD WIND FIELD FROM THE PARENT TROPICAL WAVE RESPONSIBLE FOR THIS WAVE ENERGY THAT WILL SPREAD NW AND ACROSS THE OFFSHORE WATERS N AND NE OF THE LEEWARDS NEXT 24-36 HOUR. NOTE...GRIDDED MARINE FORECAST IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .TROPICAL STORM WARNING...AMZ025-035. SW N ATLANTIC... .TROPICAL STORM WARNING...AMZ125-127. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER STRIPLING