000 AGXX40 KNHC 282001 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 255 PM EST WED DEC 28 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... NOW THAT THE COLD FRONT THAT MOVED ACROSS THE GULF YESTERDAY AND EARLY THIS MORNING HAS EXITED THE GULF...HIGH PRES HAS TAKEN OVER AS THE MAIN FEATURE TO IMPACT THE WIND REGION THROUGHOUT. RECENT BUOY REPORTS REVEAL RELATIVELY LIGHT WINDS WITH DIRECTIONS NE-E TO THE E OF 87W AND E-SE W OF 87W. THE EXCEPTION IS IN THE FAR SE PART FROM THE FLORIDA KEYS TO WESTERN CUBA WHERE WINDS ARE N AT 15-20 KT. THE BUOYS ARE REPORTING WAVE HEIGHTS OF 3-5 FT E OF 90W S OF 26N...AND 2-4 FT ELSEWHERE EXCEPT 1-2 FT IN THE FAR NW PORTION. SEAS MAY BE UP TO 6 FT IN THE FAR SE WATERS...ESPECIALLY IN THE STRAITS OF FLORIDA. THESE VALUES ARE IN REASONABLE CLOSE AGREEMENT WITH THE WAVEWATCH MODEL GUIDANCE...WITH THE EXCEPTION OF THE SRN PORTION OF THE MIDDLE GULF AND MOST OF THE SRN PORTION OF THE EASTERN GULF (EXCEPT AS POINTED OUT ABOVE) WHERE THE MODEL IS SLOW IN REDUCING THE SEA HEIGHTS. MODELS FORECAST THE HIGH PRES OVER THE AREA TO SLIDE EASTWARD TO E OF THE GULF BY SUN. THIS WILL ALLOW FOR THE NEXT COLD FRONT TO MOVE INTO THE WESTERN GULF SUN AFTERNOON...AND QUICKLY REACH THE NE GULF SUN NIGHT. STRONG HIGH PRES PRODUCING STRONG OFFSHORE FLOW AND BUILDING WILL FOLLOW IN THE WAKE OF THE FRONT. SOUTHWEST N ATLC S OF 31N W OF 65W... THE PRELIMINARY 18 UTC ANALYSIS HAS A COLD FRONT EXTENDING FROM 31N69W SW TO CENTRAL CUBA...WHILE A RIDGE EXTENDS E TO W INTO THE AREA ALONG 23N. BOTH HIGH RESOLUTION ASCAT DATA FROM THIS MORNING ALONG WITH BUOY OBSERVATIONS JUST N OF THE FORECAST AREA SHOWED THAT WINDS S-SW AT 20-30 KT E OF FRONT N OF 28N...WHILE SW 15-20 KT WINDS ARE ELSEWHERE E OF THE FRONT N OF 25N. VISIBLE SATELLITE IMAGERY IS DISPLAYING COLD AIR STRATOCUMULUS CLOUDS IN THE WAKE OF THE FRONT N OF THE BAHAMAS. WINDS THERE ARE NW 15-20 KT...EXCEPT N OF 27N BETWEEN THE FRONT AND 76W WHERE STRONGER WINDS W TO NW IN DIRECTION AT 20-25 KT ARE NOTED. SEAS RANGE FROM 8-13 FT E OF THE FRONT N OF 28N...TO 6-8 FT ELSEWHERE E OF THE FRONT PRIMARILY DUE TO A N SWELL AND 5-8 FT W OF THE FRONT EXCEPT 10-14 FT IN A NW SWELL N OF 28N BETWEEN THE FRONT AND 75W. SCATTERED SHOWERS AND ISOLATED WEAK TSTMS ARE SEEN ALONG AND WITHIN ABOUT 75 NM E OF THE FRONT. THE FORECAST CALLS FOR THE FRONT TO QUICKLY MOVE E TO A LINE FROM 28N65W TO CENTRAL CUBA THU THEN WEAKEN THU NIGHT...AND LIFT NORTHWARD AS A FRONTAL TROUGH FROM 30N65W TO STRAITS OF FLORIDA BY FRI NIGHT. WEAK HIGH PRESS WILL BUILD ACROSS THE AREA SAT AND SUN ALLOWING FOR GENERALLY LIGHT WINDS THROUGHOUT. HOWEVER...A STRONGER SURGE OF HIGH PRES WILL BUILD INTO MUCH OF THE WESTERN PORTION OF THE ON MON INDUCING A TIGHTER GRADIENT WITH INCREASING NW-N WINDS OF POSSIBLY IN THE RANGE OF 20-25 KT. THESE WINDS MAY INCREASE TO 30 KT OVER THE FAR NW WATERS LATE MON INTO TUE AS NOW THE LATEST ECMWF RUN SUGGESTS THESE SPEEDS. CARIBBEAN SEA AND TROPICAL N ATLC... HIGH PRES CENTER OVER SW N ATLC WEAKENS AND SHIFT E AS COLD FRONT MOVES INTO ATLC RESULTING IN RELAXING PRES GRADIENT OVER CARIBBEAN. HOWEVER 20-25 KT WINDS WITH SEAS TO 10 FT WILL REMAIN ACROSS THE S CENTRAL CARIBBEAN WITH WINDS TO 30 KT ALONG THE COAST OF COLOMBIA EXPECTED TO LAST INTO MON AS HIGH PRES REBUILDING N OF AREA TIGHTENS THE PRES GRADIENT ACROSS MOST OF THE AREA. LONG PERIOD N SWELLS WILL RESULT IN RATHER ROUGH SE CONDITIONS OVER MOST OF THE TROPICAL N ATLC AND NE CARIBBEAN SEA THROUGH LATE SAT BEFORE SUBSIDING. WARNINGS... GULF OF MEXICO... .NONE. .CARIBBEAN SEA AND TROPICAL N ATLC... .NONE . .SW N ATLC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER DGS