000 AGXX40 KNHC 060800 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 230 AM EST MON DEC 6 2010 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... COLD FRONT RAPIDLY MAKING PROGRESS ACROSS THE SOUTHERN HALF OF THE GULF EARLY THIS MORNING...AND EXTENDS FROM THE WESTERN STRAITS OF FLORIDA W TO 24N90W AND NW TO A POSSIBLE DEVELOPING WEAK LOW NEAR 24N96W AS NOTED ON SATELLITE IMAGERY...AND AS ALSO HINTED ON A VERY SMALL PARTIAL ASCAT PASS FROM 0414 UTC. STRONG HIGH PRES IS BUILDING S ACROSS THE AREA IN THE WAKE OF THE FRONT BRINGING IN MODERATE NORTHERLY FLOW AS EVIDENT BY REPORTS FROM BUOYS STATIONS N OF THE FRONT WHERE WINDS ARE N-NE 20-25 KT E OF 91W AND NE 15-20 KT W OF 91W. SEAS RANGE FROM 6-9 FT IN THE CENTRAL GULF TO 2-4 FT ELSEWHERE N OF 24N...AND TO 1-2 FT S OF 24N. THE FRONT WILL ENTER THE NW CARIBBEAN SEA TONIGHT WITH ITS FAR WESTERN EXTENSION HANGING UP OVER THE FAR WESTERN GULF AS A TROUGH WITH POSSIBLE LOW PRES IF DOES MATERIALIZE AS MENTIONED ABOVE. EXPECT THE CURRENT NORTHERLY FLOW TO DIMINISH TO 10-15 KT ACROSS MUCH OF THE AREA BEGINNING TONIGHT AND TUE...WITH N WINDS IN THE OF 15-20 KT OVER THE EASTERN PORTION THEN DIMINISHING TO 10-15 KT TUE NIGHT AS HIGH PRES CENTERED N OF THE AREA SHIFTS E TO THE EASTERN SEABOARD. WINDS VEER AROUND TO E-SE GOING INTO THE MIDDLE TO LATTER PART OF THE WEEK WITH THE HIGH SHIFTING E. QUESTION MARKS REMAIN WITH WINDS ASSOCIATED WITH POTENTIAL W GULF LOW E OF NE MEXICO MATERIALIZING ON THE TAIL END OF THE FRONT DURING THE WEEK. LATEST RUN OF THE MODELS HINT AS SOME FORM OF WEAK LOW OR FRONTAL WAVE FORMING THERE. LATEST GFS RUN IS STILL QUITE AGGRESSIVE WITH THIS SCENARIO SUGGESTING INCREASING NORTHERLY WINDS BETWEEN THE LOW AND SOUTHERN TEXAS AND MEXICAN COASTS WED AND THU. UKMET IS SOMEWHAT SIMILAR TO GFS WITH WINDS OF 20-25 KT IN THE FAR WESTERN GULF WED AND THU. THE ECMWF SHOWS THESE WINDS MAINLY IN THE WESTERN PART OF THE SW GULF WED AND THU. WILL LEAN TOWARD THESE WINDS FOR THIS FORECAST PACKAGE WITH SEAS UP TO AROUND 7 OR 8 FT BY THU. CARIBBEAN AND TROP N ATLC S OF 22N W OF 55W... NE WINDS OF 10-15 KT ARE BEING REPORTED BY BUOYS THROUGHOUT EXCEPT FOR THE CENTRAL SECTION OF THE SEA WHERE AN ASCAT PASS ALONG WITH A COUPLE OF SHIP OBSERVATIONS REVEALED NE WINDS OF 20 KT AS WELL AS FOR WATERS SE OF OF HISPANIOLA AND BETWEEN JAMAICA AND THE WINDWARD PASSAGE. THESE WINDS SHOULD THROUGH FRI AS A TIGHT PRES GRADIENT BETWEEN HIGH PRES BUILDING SE ACROSS THE NW CARIBBEAN AND LOW PRES OVER THE FAR SOUTHERN CARIBBEAN AND S AMERICA SUPPORT THE WINDS. WINDS INCREASE TO N 15-20 KT OVER THE NW PORTION OF THE SEA LATER THIS MORNING AND AFTERNOON AS THE GULF OF MEXICO PUSHES INTO THE AREA. THE FRONT WILL QUICKLY MOVE THROUGH THE NORTHERN AND CENTRAL CARIBBEAN TONIGHT THROUGH WED BEFORE STALLING AND WEAKENING TO A FRONTAL TROUGH OVER THE NE WATERS THU AND FRI. WAVEWATCH GUIDANCE INDICATES THAT SEAS BUILD UP TO 10 FT IN THE FAR SW WATERS LATE WED THROUGH THU ...AND TO 11 FT BY LATE THU AND FRI. BUOYS N OF THE AREA IN THE ATLC INDICATE THAT A BATCH OF N SWELLS RESULTING IN SEAS IN THE RANGE OF 8-10 FT WILL SURGE S INTO THE NORTHERN TROPICAL N ATLC WATERS TODAY...AND TO REMAINDER OF THOSE WATERS TONIGHT THROUGH TUE NIGHT. BY WED YET ANOTHER SURGE OF SWELLS FROM THE NE WILL MIX WITH THE N SWELLS RESULTING IN SEAS UP TO 11 FT TO INVADE MOST OF THE TROPICAL N ATLC THU AND FRI PER WAVEWATCH GUIDANCE. SWELLS WILL ALSO AFFECT THE ATLC PASSAGES THROUGH THIS PERIOD. SW N ATLC W OF 65W... STRONG LOW PRES WELL N OF THE AREA HAS PUSHED A COLD FRONT INTO THE AREA FROM 28N65W SW TO S FLORIDA EARLY THIS MORNING. THE FRONT WILL REACH A POSITION FROM 28N65W TO CENTRAL CUBA THIS AFTERNOON...THEN BEGIN TO SLOW ITS PROGRESS AS IT REACHES FROM NEAR 27N65W TO HISPANIOLA TONIGHT INTO TUE...AND SLOWLY DISSIPATE OVER THE FAR SE WATERS WED THROUGH FRI AS HIGH PRES SETTLES IN OVER THE AREA. COLD AIR ADVECTION WILL ONCE AGAIN FUNNEL IN ACROSS THE AREA BEHIND THE FRONT THROUGH WED. A FAIRLY TIGHT PRES GRADIENT AS A RESULT OF LARGE LOW PRES N OF THE AREA AND HIGHER PRES THAT BUILDS SE BEHIND THE FRONT WILL W-NW WINDS OF 20-25 KT N OF 26N INTO TUE NIGHT...WITH WINDS UP TO 30 KT E OF 71W THROUGH TUE. UPSTREAM BUOY 41048 AT 32N69.5W IS REPORTING COMBINED SEAS OF 15 FT...AND WAS RECENTLY UP TO 17 FT IN NW SWELLS. EXPECT THESE LARGE SWELLS TO CONTINUE TO AFFECT THE NE WATERS THROUGH WED AFTERNOON BEFORE SUBSIDING TO AROUND 10 FT. WINDS QUICKLY DIMINISH TO NW 10-15 KT WED EXCEPT TO NW-N 5-10 KT TO THE W OF 71W. WINDS OVER THE SOUTHERN HALF OF THE AREA WILL BE N-NE 10-15 KT BY WED WITH THE MAIN ISSUE OF N SWELLS...UP TO 8 OR 9 FT AFFECTING THE SE WATERS TO THE E OF THE BAHAMAS. WAVEWATCH GUIDANCE SHOWS SEAS SUBSIDING TO 2-3 FT OVER THE FAR WESTERN WATERS WED. ON THU WINDS VEER AROUND TO THE NE-E AT 10 KT OVER THE EASTERN HALF OF THE AREA WITH LARGE MIXED N AND NE SWELLS LEADING TO SEAS OF 8-10 FT THERE. WITH PRES GRADIENT TIGHTENING BETWEEN THE FRONT OVER THE SE PORTION AND STRONG HIGH PRES BUILDING SE ACROSS THE REMAINDER OF THE AREA...WINDS INCREASE TO NE 20-25 KT ACROSS THE EASTERN PORTION FUNNELING SE TOWARDS THE WATERS BETWEEN THE BAHAMAS HISPANIOLA INCLUDING THE WINDWARD PASSAGE. OVER THE REMAINDER OF THE AREA ON FRI...WINDS ARE EXPECTED TO BE FROM THE NE AT ABOUT 15 KT...WITH LIGHTER SPEEDS OVER THE FAR NW PORTION AS A N TO S TROUGH DEVELOPS N OF THE BAHAMAS. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE