000 AGXX40 KNHC 131859 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 246 PM 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... LARGE 1032 MB SURFACE HIGH OVER PENNSYLVANIA WITH ASSOCIATED SURFACE RIDGE EXTENDING DOWN TO THE NE GULF MAINTAINS FRESH TO LOCALLY STRONG NE TO NNE FLOW OVER THE EASTERN GULF. A 1545 UTC ASCAT PASS INDICATED A SOLID AREA OF 20 TO LOCALLY 25 KT WINDS OVER THE GULF E OF 86W. AS NOTED IN THE PREVIOUS DISCUSSION...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 LOCALLY IN EXCESS OF 10 FT. SGFNT WAVE HEIGHT GRIDS WERE ADJUSTED ACCORDINGLY FOR THE FIRST TWO PERIODS TO REFLECT HIGHER SEAS IN THE WIND AGAINST CURRENT REGION. WINDS GRADUALLY WEAKEN TO 15 KT AND BACK TO THE NORTH SUN AND MON WITH WINDS MORE OBLIQUE TO THE CURRENT AND SEAS MORE IN LINE WITH THE WW3 OUTPUT. PREFER GFS/NOGAPS AND LESSER EXTENT UKMET SOLUTION OF A DIGGING NEG TILT SHORTWAVE TROUGH SWEEPING THROUGH THE TENN VALLEY INTO THE MID-ATLC BY 12Z TUE WHICH DROPS A COLD FRONT INTO THE FAR NRN GULF BY MON EVENING AND EXTENDS ACROSS THE GULF N OF 25N E OF 90W BY LATE TUE. WINDS ONCE AGAIN INCREASE TUE TO 15-20 KT THEN DECREASE WED AND THU. MODERATE SE RETURN FLOW OVER THE GULF W OF 90W WEAKENS SUN AND SHIFTS TO THE NW ALBEIT IN THE 10-15 KT RANGE IN THE WAKE OF THE AFOREMENTIONED FRONTAL PASSAGE. WINDS VEER MORE TO THE E TUE AND MODERATE RETURN FLOW ENSUES WED AND THU BEFORE A STRONGER COLD FRONT EMERGES OFF THE TEXAS COAST LATE THU. SW N ATLC S OF 31N W OF 65W... ELONGATED LLVL TROUGHING AND MERGED FRONTAL ZONE EXTENDS FROM 31N66W TO ERN CUBA. STRONG UPPER LEVEL SHEAR AND STRETCHING FINALLY FINISHED OFF PATTY AS OF 15 UTC. THE REMNANT TROUGH SHOULD SHIFT SW ACROSS THE S CENTRAL BAHAMAS TONIGHT AND THEN INTO CUBA SUN. STRONG GRADIENT TO THE W AND NW OF THE FRONTAL ZONE IS YIELDING NNE TO NE WINDS 20-25 KT ACROSS MUCH OF THE WATERS TO THE W OF THE FRONT...AND 25-30 KT WITHIN 150 NM OF THE FRONTAL ZONE N OF 27N PER A 1452 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 OF 30 KT IN THE NW BAHAMAS PAST FEW HOURS. BUOY 41047 CURRENTLY REPORTING 11 FT SEAS WHERE NWW3 DEPICTS A FORECAST OF 8-9 FT. THUS IT APPEARS ONCE AGAIN SEAS ARE VERY UNDERDONE BY THE NWW3 BY ABOUT 1-3 FT. IN ANY EVENT A BROAD ZONE OF 8-10 FT WITH AREAS OF 11-12 FT SEAS IN BANDS OF HIGHER WINDS ARE OCCURRING. THIS WAVE ACTION SLAMMING INTO ATLC COASTS OF NW AND CENTRAL BAHAMAS AND EXPECTED TO PEAK THIS 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 E TO SE 20-25 KT WINDS IN THE WAKE OF THE STORM ARE SPREADING NW ACROSS THE ATLC WATERS N AND NE OF THE LESSER ANTILLES...WITH BUILDING SEAS ACROSS ATLC E OF 68W. A 1314 UTC ASCAT PASS CAPTURED 20-25 KT WINDS WITH AN AREA OF 30 KT WINDS OVER THE LESSER ANTILLES FROM ST. LUCIA NORTHWARD TO ANTIGUA. 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. LATEST VISIBLE SATELLITE IMAGERY INDICATES THE WIND SHEAR OVER RAFAEL MAY BE LESSENING WITH EVIDENCE OF DEEP CONVECTION DEVELOPING CLOSER TO THE LOW LEVEL CENTER AND SOME STRENGTHENING IS EXPECTED OVER THE NEXT 48-72 HOURS...WITH RAFAEL POSSIBLY BECOMING A HURRICANE. 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. GFS NWP SOLUTION APPEARS TO BE THE CLOSEST TO THE NHC OFFICIAL TRACK FORECAST. GIVEN THE PREFERENCE FOR ITS UPPER LEVEL SOLUTION...I THEREFORE UTILIZED A BLEND OF THE GFS AND THE OFFICIAL FORECAST IN THE GFE GRIDS. NWW3 SGFNT WAVE HEIGHT FIELDS WELL REPRESENT THE LARGE CIRCULATION OF RAFAEL AND ONLY SLIGHT ADJUSTMENTS WERE MADE TO THE SGNFT WAVE HEIGHT FIELDS TO BRING THEM MORE IN LINE WITH THE OFFICIAL TCM FORECAST. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... AS NOTED ABOVE LATEST SATELLITE IMAGERY INDICATES THE WIND SHEAR OVER RAFAEL MAY BE LESSENING WITH EVIDENCE OF DEEP CONVECTION DEVELOPING CLOSER TO THE LOW LEVEL CENTER. NONETHELESS THE VAST MAJORITY OF WINDS AND WEATHER ASSOCIATED WITH THE STORM REMAIN OVER THE BROAD E SEMICIRCLE OF THE 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. 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 CONTINUES TO REPORT 10-11 FT SEAS WITH 12 FT SEAS LIKELY TO THE 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 HOURS. 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...AMZ023...AMZ025...AMZ035 SW N ATLANTIC... .TROPICAL STORM WARNING...AMZ125...AMZ127. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER COBB