000 AGXX40 KNHC 080648 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 148 AM EST SAT DEC 08 2007 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. ATLANTIC... THE ANTICIPATED WIND/SWELL EVENT IS BEGINNING TO TAKE SHAPE FOR THE SOUTHERN PART OF THE SW N ATLC ZONE AS HIGH PRES BUILDS ALONG 31N AND A SURFACE TROUGH IN THE TROPICAL EASTERLIES NEAR 52W APPROACHES FROM THE EAST. A RECENT ASCAT PASS AND OBSERVATIONS FROM BUOYS 40143 AND 41046 INDICATE THAT WINDS HAVE INCREASED TO 15-20 KT OVER THE SE PORTION WITH GRADUALLY BUILDING SEAS. WINDS ARE EXPECTED TO INCREASE FURTHER TO 20-25 KT BY TONIGHT THEN TO 25-30 KT BY SUN EVENING AS THE PRES GRADIENT TIGHTENS. LIKE LAST NIGHT...THE 00Z GFS IS SHOWING A FEW 35 KT BARBS N OF PUERTO RICO AROUND MON MORNING BUT THE OTHER GLOBAL MODELS...AS WELL AS THE ENSEMBLES...ARE STILL NOT BUYING INTO THIS SCENARIO. IT IS ENTIRELY POSSIBLE THAT WINDS COULD GUST TO GALE FORCE OVER THE SE PORTION ON MON BUT FOR NOW WILL CONTINUE THE FCST OF 25-30 KT UNTIL AND IF STRONGER EVIDENCE SHOWS OTHERWISE. THE STRONGEST WINDS SHIFT W ACROSS THE BAHAMAS ON TUE IN TANDEM WITH THE TROUGH...WHICH WILL BE MOVING ACROSS THE CARIBBEAN WATERS...BUT THEN ENSEMBLE GUIDANCE INDICATES THAT THE GRADIENT WILL LIKELY RELAX A BIT ON WED AS THE SURFACE HIGH NEAR 30N BREAKS DOWN. SWELLS WILL BE A BIG ISSUE DURING THIS EVENT AS THE ZONE OF HIGH WINDS TREKS WESTWARD FROM THE CENTRAL ATLC TO THE BAHAMAS...PRODUCING A DYNAMIC FETCH OF WINDS OVER A SEVERAL DAY PERIOD. THE FCST WILL CONTINUE MENTION OF SEAS TO 16 FT MON AND TUE...VERY CLOSE TO WW3 AND UKMET WAVE GUIDANCE. CARIBBEAN AND TROPICAL N ATLC... WINDS ARE PICKING UP AS WELL OVER THE E AND CENTRAL CARIBBEAN AS THE SURFACE TROUGH APPROACHES FROM THE EAST. BUOY 42059 S OF PUERTO RICO IS REPORTING MAXIMUM 1-MIN WINDS OF 23 KT AND SEAS HAVE ALREADY BUILT TO 9 FT...WHICH IS JUST SLIGHTLY HIGHER THAN CURRENT WW3 GUIDANCE. THE STRONG 20-25 KT WINDS WILL CONTINUE OVER THE REGION FOR THE NEXT FEW DAYS AND WILL SPREAD A LITTLE FARTHER W INTO THE W CARIBBEAN. IN ADDITION...THE AREA JUST S OF THE DOMINICAN REPUBLIC WILL LIKELY SEE AN ACCELERATION OF THE FLOW DOWNSTREAM OF THE MONA PASSAGE...AND WINDS WILL BE IN THE 25-30 KT RANGE AT LEAST THROUGH SUN/SUN NIGHT. WIND ACCELERATION IS ALSO EXPECTED THROUGH THE WINDWARD PASSAGE WHERE WINDS ARE ALREADY 20-25 KT AND WILL LIKELY INCREASE TO 30 KT TONIGHT THROUGH MON NIGHT. IN THE EXTENDED PERIOD...THE STRONGEST PART OF THE PRES GRADIENT SHIFTS N OF THE GREATER ANTILLES ON MON WHICH WILL ALLOW WINDS TO DIMINISH A BIT OVER THE CARIBBEAN WATERS. THE BREAK WILL BE RELATIVELY SHORT-LIVED OVER THE TROPICAL N ATLC WATERS WHERE WINDS WILL INCREASE ONCE AGAIN INTO THE 20-25 KT RANGE TUE AND WED N OF 12N AS HIGH PRES BUILDS OVER THE CENTRAL ATLANTIC. GULF OF MEXICO... A SURFACE RIDGE HAS TAKEN HOLD OVER THE GULF WITH EASTERLY WINDS OVER THE STRAITS OF FLORIDA TRANSITIONING TO SE/SOUTHERLY WINDS NEAR THE TEXAS AND LOUISIANA COASTS. WINDS ARE OCCASIONALLY REACHING 20 KT OFF THE TEXAS COAST IN RETURN FLOW AND THIS WILL LIKELY CONTINUE AT LEAST THROUGH TUE BEFORE THE NEXT COLD FRONT MOVES ACROSS TEXAS AND APPROACHES THE COAST. ALSO...A FEW SHIP REPORTS OVER THE STRAITS OF FLORIDA INDICATE THAT WINDS ARE ALREADY INCREASING TO 15-20 KT AND SHOULD HOLD THROUGH THE FORECAST PERIOD...POSSIBLY INCREASING TO 20-25 KT ESPECIALLY SUN AND MON. WW3 GUIDANCE STILL BARELY BUILDS SEAS TO 8 FT...WHICH SEEMS UNREASONABLE GIVEN AN UNHINDERED EASTERLY FETCH...SO THE FCST WILL CONTINUE TO GO A FEW FEET ABOVE THAT. NO CHANGES TO THE OVERALL PATTERN ARE EXPECTED UNTIL WED WHEN MODEL GUIDANCE IS IN DECENT TIMING AGREEMENT THAT A COLD FRONT WILL MOVE OFF THE TEXAS COAST WED EVENING. EVEN THOUGH THE TIMING OF THE FRONT IS AGREED UPON...THE MODELS ARE IN DISAGREEMENT ON THE STRENGTH OF THE FRONT. FOR NOW...WILL CALL FOR WINDS TO TURN NORTHERLY AT 15-20 KT IN LINE WITH THE GFS AND ECMWF...AND THE 20-30% PROBABILITY OF 20 KT WINDS SHOWN BY THE GFS ENSEMBLE. WARNINGS... ATLANTIC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. FORECASTER BERG