000 AGXX40 KNHC 310737 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 230 AM EST SAT DEC 31 2011 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... A 1021 MB HIGH CENTER IS ANALYZED ON THE PRELIMINARY 6 UTC ANALYSIS TO BE NEAR 26N87W WITH A RIDGE EXTENDING WESTWARD TO 26N94W. RECENT BUOY OBSERVATIONS ACROSS THE GULF SHOW S-SW WINDS OF 10-15 KT N OF 27N...SE-S WINDS OF 5-10 KT FROM 25N-27N AND E-SE WINDS OF 10-15 KT S OF 25N W OF 85W. NE WINDS OF 15-20 KT ARE CONFINED TO THE FAR SRN WATERS OF THE MIDDLE JUST TO THE ENTRANCE OF THE YUCATAN CHANNEL AND ALONG THE TIP OF WRN CUBA. OBSERVED SEA STATE HAS VALUES IN THE 1-3 FT RANGE...WITH THE EXCEPTION OF THE FAR SRN WATERS OF THE MIDDLE GULF WHERE HIGHER VALUES OF 3-5 FT ARE SEEN ESPECIALLY AT THE ENTRANCE TO THE YUCATAN CHANNEL WHERE A FEW SHIP REPORTS THERE REVEALED MAX SEAS OF 5 FT. NEAR FUTURE UPCOMING CHANGES REGARDING THE GULF OF MEXICO FORECAST STILL HOLD AS ADVERTISED IN FORECASTS FROM PREVIOUS DAYS. THE 1021 MB HIGH WILL SHIFT E SUN TO E OF AREA BY SUN EVENING. THIS WILL ALLOW FOR A COLD FRONT TO MOVE OFF THE TEXAS AND SW LOUISIANA COASTS INTO THE FAR NW GULF WATERS EARLY SUN AS DEPICTED IN THE MODEL GUIDANCE. THE COLD FRONT WILL QUICKLY MOVE ACROSS THE GULF...REACHING FROM FROM SE LOUISIANA TO THE TEXAS/MEXICO BORDER EARLY SUN...AND FROM NEAR NAPLES FLORIDA TO 23N95W TO 19N95W BY EARLY ON MON. THE FRONT WILL THEN MOVE SE OF THE GULF EARLY MON EVENING. THE FIRST STRONG HIGH PRES AREA TO BE SEEN THIS EARLY IN THE WINTER SEASON WILL BUILD ACROSS THE ENTIRE GULF IN THE WAKE OF THE FRONT RESULTING A VERY TIGHT PRES GRADIENT THAT WILL BE MORE NOTICEABLE IN THE WRN SECTION ...PARTICULARLY THE SW ZONE. RESULTANT N-NE WINDS OF 20-25 KT WILL OVERSPREAD THE GULF INTO MUCH OF TUE AT WHICH TIME WINDS BEGIN TO DIMINISH FROM W TO E AS A HIGH PRES CENTER MOVES ACROSS EASTERN TEXAS. NW-N GALE FORCE WINDS OF 30-35 KT ARE STILL EXPECTED IN THE SW GULF W OF ABOUT 95W ON MON DUE TO STRONG COLD AIR ADVECTION NUDGING SWD TIGHT PRES GRADIENT ALONG THE MEXICAN COAST. THE LATEST GFS/ECMWF RUNS CONSISTENTLY AGREE ON GALE FORCE WINDS FOR THAT PART OF THE GULF ON MON. IN ADDITION...THE SREF PROBABILITIES ARE ABOUT 50 PERCENT FOR THAT SAME TIME AND LOCATION. HOWEVER...IT APPEARS THE GALE FORCE WINDS WILL BE RATHER SHORT-LIVED WITH WINDS FORECAST TO DROP BELOW GALE FORCE LATE ON MON. THERE MAY BE BRIEF INSTANCES OF WINDS GUSTING TO NEAR 30 KT OVER THE FAR WESTERN GULF WATERS ON SUN MORNING. SW N ATLC S OF 31N W OF 65W... THE 6 UTC PRELIMINARY SURFACE ANALYSIS SHOWS A DISSIPATING WARM FRONT EXTENDING INTO THE AREA FROM NEAR 31N71W TO 28N74W...AND A WEAK INVERTED TROUGH ALONG 27N67W TO 23N71W. SCATTERED SHOWERS AND WEAK ISOLATED TSTMS ARE ALONG WITHIN 90 NM SE OF THE TROUGH. A WEAK RIDGE IS ALONG 26N. TO THE S OF THE RIDGE AND TROUGH E-SE 10-15 KT WINDS ARE NOTED. THE ASCAT PASS FROM 0124 UTC LAST NIGHT REVEALED AN AREA OF E-SE 15-20 KT WINDS S OF 21N AND E OF THE SE BAHAMAS. WINDS N OF THE RIDGE AND TROUGH ARE S-SW 10-15 KT W OF 75W...AND LIGHT AND VARIABLE AT 5-10 KT E OF 75W. LATEST AND CURRENT BUOY OBSERVATIONS HAVE SHOWN AND ARE PRESENTLY SHOWING SEAS OF 7 FT IN N SWELLS OVER THE SRN SECTION OF THE AREA S OF ABOUT 22N AND E OF THE SE BAHAMAS. SEAS ELSEWHERE ARE IN THE RANGE OF 4-6 FT PRIMARILY IN N SWELLS NE OF THE TROUGH AND 2-4 FT NW OF THE TROUGH. THE N SWELLS OF 7 FT WILL BE REPLACED BY A NEW BATCH OF E SWELLS ARRIVING FROM THE FAR EASTERN AND CENTRAL ATLC TODAY THROUGH EARLY TUE WHICH WILL BRING SEAS THERE BACK UP TO 8 OR 9 FT PER WAVEWATCH GUIDANCE. SEAS THEN SUBSIDE LATER TUE AND WED. THE STRONG COLD FRONT FORECAST TO SWEEP ACROSS THE GULF OF MEXICO AS DESCRIBED ABOVE IS STILL SUGGESTED BY THE MODELS THAT IT MOVES INTO THE NW PORTION OF THE AREA ON SUN NIGHT. THE FRONT WILL MOVE TO POSITION FROM NEAR 31N72W TO CENTRAL CUBA BY MON AFTERNOON...AND OVER THE FAR SE PORTION OF THE AREA LATE ON TUE BEFORE MOVING E OF THE AREA WED. NW TO N WINDS WILL INCREASE TO 20-25 KT W OF THE FRONT THROUGH EARLY TUE...WITH POSSIBLE W-NW GALE WINDS N OF 28N BETWEEN THE FRONT AND 78W AND ALSO E OF THE FRONT N OF 28N AS STRONG HIGH PRES BUILDS E OVER THE AREA. SEAS ARE EXPECTED TO BUILD TO QUITE LARGE VALUES... PERHAPS TO 15-17 FT BEHIND THE FRONT OVER THE WATERS NE OF THE BAHAMAS ON TUE. WINDS AHEAD OF THE FRONT WILL BECOME SW AND INCREASE TO 15-20 KT ON MON...THEN TO 20-30 KT LATE MON AND TUE N OF 27N. ON WED HIGH PRES BUILDS FURTHER EASTWARD ACROSS THE MUCH OF THE AREA ALLOWING FOR WINDS TO ABATE IN THE CENTRAL AND WESTERN PORTIONS. A LINGERING TIGHT PRES GRADIENT IN THE SE PORTION WILL ALLOW FOR N-NE 20 KT TO LINGER THERE WED. THE MAIN ISSUE GOING INTO WED WILL BE LINGERING LARGE NW SWELLS WITH PRODUCING SEAS IN THE 15-19 FT RANGE OVER MOST OF THE WATERS E OF 71W. CARIBBEAN SEA AND TROPICAL N ATLC... BUOY OBSERVATIONS SHOW NE-E WINDS OF 20 KT THROUGHOUT THE TROPICAL N ATLC...AND IN THE CENTRAL PORTION OF THE CARIBBEAN SEA. PARTIAL ASCAT DATA FROM LAST NIGHT SHOWED SIMILAR WINDS. WINDS MAY BE UP TO 30 KT ALONG AND VERY NEAR THE COAST OF COLOMBIA. WINDS ELSEWHERE IN THE CARIBBEAN ARE NE-E 10-15 KT ...EXCEPT E 15-20 KT IN THE NE PORTION. SEAS ARE HIGH...UP TO 8-12 FT IN THE TROPICAL N ATLC AND TO 7 FT THROUGH NE PASSAGES IN THE NE CARIBBEAN DUE TO LARGE N SWELLS. SEAS ELSEWHERE ARE IN THE 3-6 FT RANGE. COLD FRONTS WILL MOVE INTO THE ATLC WATERS N OF THE AREA WITH HIGH PRES BEHIND THEM TIGHTENING THE PRES GRADIENT RESULTING IN INCREASING NE-E WINDS OVER THE WEEKEND STILL ON TAP AS STATED IN PREVIOUS FORECASTS. THE GULF OF MEXICO COLD FRONT WILL ILL MOVE INTO THE NW CARIBBEAN MON...REACHING FROM EASTERN CUBA TO THE SW CARIBBEAN TUE. THE FRONT WILL STALL FROM CENTRAL HISPANIOLA TO THE CENTRAL SW CARIBBEAN WED. NE-E TRADES TRADES WILL INCREASE TO 25-30 KT OVER THE S CENTRAL CARIBBEAN AND 20-25 KT ELSEWHERE S OF 18N E OF 83W BY LATE SUN. SEAS SHOULD BUILD TO 14 OR 15 FT IN THE SW CARIBBEAN THROUGH SUN NIGHT WITH THE LONG E FETCH OF THE 25-30 KT WINDS. N-NE WINDS OF 20-25 KT WILL FOLLOW IN BEHIND THE COLD FRONT WITH SEAS BUILDING UP TO AROUND 11 FT. WARNINGS... GULF OF MEXICO... .GMZ082...GALE CONDITIONS EXPECTED W OF 95W MON.. .CARIBBEAN SEA AND TROPICAL N ATLC... .NONE . .SW N ATLC... .AMZ080...GALE CONDITIONS EXPECTED N OF 28N W OF FRONT TO 78W TUE AND N OF 28N E OF FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE