000 AGXX40 KNHC 121858 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 300 PM EDT FRI OCT 12 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... HIGH PRES RIDGE ACROSS EASTERN U.S. REMAINS IN PLACE EARLY THIS MORNING AND IS COMBINING WITH ELONGATED TROUGHING AND WEAKENING T.S. PATTY TO PRODUCE FRESH NELY FLOW ACROSS THE BAHAMAS AND THE FLORIDA STRAITS. LATEST BUOY OBSERVATIONS INDICATE NE WINDS OF 10 TO 15 KT AND SEAS OF 4-5 FT OVER THE GULF E OF 90W WITH 20 KT WINDS CONFINED TO THE STRAITS OF FLORIDA AND THE FLORIDA KEYS. AS NOTED EARLIER BUOYS NOT IN STRATEGIC LOCATIONS TO REVEAL TRUE SEASTATE. HOWEVER A 0940 UTC ALTIMETER PASS INDICATED 6-7 FT SEAS IN THE FLORIDA STRAITS NEAR 23N83W. 1030-1035 MB HIGH MOVING FROM THE GREAT LAKES THROUGH THE MID ATLC REGION SAT WILL MAINTAIN GRADIENT ACROSS THE NW BAHAMAS AND FLORIDA...AND CONTINUE TO PRODUCE 15-20 KT NELY WINDS ACROSS THE SE GULF VEERING MORE ENE N OF THE YUCATAN. THE LOW LEVEL CENTER OF T.S. PATTY HAS BEEN EXPOSED AND THE STORM IS WEAKENING. IF IT DOES NOT BECOME COMPLETELY SHEARED AND MOVES ON THE FORECAST SW PATH TOWARD CUBA DURING THE NEXT 48 HRS...IT WILL AID IN MAINTAINING GRADIENT. THE 12Z GFS AND THE 12Z ECMWF SHOW REASONABLE AGREEMENT ON A SOLID AREA OF 25 KT WINDS IN THE STRAITS OF FLORIDA SAT NIGHT...WITH WINDS DIRECTLY AGAINST THE FLORIDA CURRENT THAT COULD YIELD SEAS 10-12 FT AT THAT TIME. THE GFS HOLDS ONTO THE PATTY REMNANTS INTO NEXT WEEK AS THEY MOVE INTO THE NW CARIBBEAN WHILE THE ECMWF DIMINISHES THE SYSTEM. CONFIDENCE IS LOW ON ITS SURVIVAL. THIS MAKES A DIFFERENCE IN THE FORECAST OVER THE SE GULF WHERE THE FRESH BREEZE IN THE GFS IS 5-10 KT STRONGER THAN THE ECMWF. WITH CONFIDENCE LOW WITH PATTY...A BLEND OF THE GFS AND ECMWF SEEMS APPROPRIATE HERE. THIS BLEND WAS APPLIED TO THE REMAINDER OF THE GULF WHERE WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA MON THROUGH WED. SW N ATLC S OF 31N W OF 65W... DISSIPATING FRONTAL ZONE IS DRAPED JUST TO THE NW OF WEAKENING T.S. PATTY WITH DEEP CONVECTION BEING SHEARED TO THE NE OF THE EXPOSED LLVL CENTER. FRESH TO LOCALLY STRONG NNE FLOW INDUCED BY TIGHT PRES GRADIENT SPILLING FROM W ATLC TO W OF PATTY AND THE NW BAHAMAS WHERE A BLEND OF THE NAH WAVE WATCH AND EARLIER SHIP OBS SUGGEST SEAS TO AROUND 12 FT SOME 180 NM W OF PATTY AND WELL REMOVED FROM T.S. WIND FIELD. COMPLEX AND COMPLICATED SCENARIO EXPECTED NEXT 48-72 HRS AS DEVELOPING LARGE AREA OF LOW PRES/TROPICAL WAVE MOVING INTO LESSER ANTILLES IMPINGES UPON ELONGATED TROUGHING THAT PATTY IS EMBEDDED WITHIN. REINFORCING HIGH MOVING E FROM THE GREAT LAKES REGION WILL FURTHER ENHANCE THIS NELY FLOW SAT AND SAT NIGHT TO MAINTAIN FRESH TO STRONG WIND FLOW AND SEAS 8-12 FT E OF BAHAMAS AND LIKELY 6-9 FT THROUGH AND IN LEE OF BAHAMAS. THE LOW/WAVE MOVING ACROSS THE LESSER ANTILLES ATTM WITH SURFACE LOW ABOUT 45 NM W OF ST LUCIA IS BEGINNING TO CONSOLIDATE AS CONVECTION IS CLOSER TO THE LLVL CENTER. IT CONTINUES TO WORK AGAINST VERY STRONG SHEAR...A HENCE DISPLACEMENT OF CNVTN TO THE E. TUTT ACROSS THE NE CARIB IS FORECAST TO SHIFT NW AND WEAKEN NEXT FEW DAYS AND ALLOW SHEAR TO RELAX AND GIVE THIS SYSTEM A CHANCE TO DEVELOP INTO A T.C. MODELS CONTINUE TO SUGGEST SIGNIFICANT DEVELOPMENT AFTER THE CENTRAL CIRCULATION CONSOLIDATES N OF THE LESSER ANTILLES SUN...THEN WILL MOVE N AND DEEPEN...MOVING THROUGH E PORTIONS OF THE AREA. SELY SWELL CURRENTLY BEGINNING TO BE GENERATED E AND NE OF THE LESSER ANTILLES WILL SPREAD INTO SE WATERS SUN. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... A BROAD AREA OF LOW PRES MOVED THROUGH THE WINDWARD ISLANDS AND WAS LOCATED ABOUT 45 NM W OF ST LUCIA AT 12Z. A LARGE 20-30 KT E TO SE WIND FIELD LIES ACROSS THE N PORTION OF THE LOW AND A VAST AREA OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS SPANS MUCH OF THE TROPICAL N ATLC AND THE ISLANDS S OF 17N. WINDS AT BARBADOS BRIEFLY REACHED TO GALE FORCE IN A THUNDERSTORM AROUND 13Z. HURRICANE HUNTER AIRCRAFT ARE CURRENTLY INVESTIGATING THE SYSTEM. THERE IS A HIGH PROBABILITY OF TROPICAL CYCLONE FORMATION WITH THIS LOW PRES AS IT TRACKS NW AT 7 KT OVER THE NEXT 48 HOURS. OTHERWISE WINDS ARE LIGHT ACROSS THE REMAINDER OF THE CARIBBEAN...WITH WINDS AND SEAS BELOW NORMAL NEXT FEW DAYS. NOTE...GRIDDED MARINE FORECAST IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .NONE. SW N ATLANTIC... .TROPICAL STORM WARNING...AMZ119. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER COBB