000 AGXX40 KNHC 090753 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 230 AM EST THU DEC 09 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... LATEST SATELLITE IMAGERY AND SURFACE PRES ANALYSIS SHOWS A LOW PRES SYSTEM NEAR 25N87W WITH A COLD FRONT SW TO INLAND THE NW YUCATAN PENINSULA AND A WITH A WARM FRONT NE TO 25N85W AND SE TO THE WESTERN STRAITS OF FLORIDA. IN THE UPPER LEVELS...A RATHER VIGOROUS MID TO UPPER LEVEL POSITIVE TILTED SHORTWAVE TROUGH SUPPORTING THIS SYSTEM IS ADVANCING EASTWARD FROM NE GULF SOUTHWESTWARD TO THE EASTERN BAY OF CAMPECHE. THIS SYSTEM WILL RAPIDLY MOVE SE REACHING NEAR W CUBA EARLY THIS AFTERNOON BEFORE DISSIPATING. N-NW WINDS BEHIND THE FRONT GUSTED TO GALE FORCE YESTERDAY OVER A PORTION OF THE SW GULF...BUT LATEST BUOY OBSERVATIONS INDICATED WINDS OF 20-30 KT BEHIND THE LOW AND FRONT EXCEPT NOW DIMINISHING TO N-NE 15 KT OVER THE WESTERN PORTION OF THE NW GULF. WINDS ELSEWHERE ARE NE 15-20 KT...EXCEPT SE 10-15 KT TO THE SE OF COLD FRONT AND E 15-20 KT S OF WARM FRONT. LATEST SEA STATE ANALYSIS SHOWED SEAS OF 9-14 FT OVER THE SW GULF...WITH SEAS OF 9-12 FT ELSEWHERE OVER THE WESTERN GULF 27N W OF 88W AND 6 TO 9 FT ELSEWHERE S OF 28N W OF 85W. OVER THE REMAINDER OF THE GULF SEAS ARE IN THE RANGE OF 4-6 FT WITH SEAS 2-3 FT E OF 85W. THE COLD FRONT WILL PUSH SE THROUGH SE WATERS THIS MORNING...AND ENTER THE NW CARIBBEAN SEA. A RIDGE WILL EXTEND SE ACROSS THE MIDDLE AND WESTERN GULF THROUGH FRI NIGHT...THEN SHIFT E THROUGH SUN AS A STRONG COLD FRONT MOVES OFFSHORE THE NW GULF COAST LATE SAT. N-NW WINDS BEHIND THE FRONT GUSTED TO GALE FORCE YESTERDAY OVER A PORTION OF THE SW GULF...BUT LATEST BUOY OBSERVATIONS INDICATE WINDS OF 20-30 KT BEHIND THE LOW AND FRONT EXCEPT NOW DIMINISHING TO N-NE 15 KT OVER THE WESTERN PORTION OF THE NW GULF. WINDS ARE EXPECTED TO REACH GALE FORCE OVER THE NORTHERN PORTIONS OF THE EASTERN GULF UNDER COLD AIR ADVECTION OF ARCTIC ORIGIN ON SUN WITH POSSIBLE FEW GUSTS TO GALE FORCE OVER THE NE PORTION OF THE MIDDLE GULF. THE FRONT WILL RAPIDLY EXIT THE GULF LATE SUN. WAVEWATCH GUIDANCE BUILDS SEAS UP TO 16 FT OVER THE SOUTHERN AND MIDDLE SECTION OF THE MIDDLE AND EASTERN GULF SUN INTO MON. SEAS SLOWLY SUBSIDE MON. CARIBBEAN AND TROPICAL N ATLC S OF 22N W OF 55W... E WINDS OF 10-15 KT ARE BEING REPORTED BY BUOYS THROUGHOUT THESE AREA EXCEPT FOR THE TROPICAL N ATLC S OF 18N AND IN THE CENTRAL AND EASTERN PORTION OF THE CARIBBEAN WHERE AN ASCAT PASS FROM LATE LAST NIGHT ALONG WITH SHIP OBSERVATIONS SHOWED N-NE WINDS OF 20-25 KT DUE TO A TIGHT PRES GRADIENT BETWEEN HIGH PRES BUILDING SE ACROSS THE NW CARIBBEAN AND A LOW PRES TROUGH LOCATED OVER THE S CENTRAL CARIBBEAN WITH A 1009 MB LOW ON THE TAIL END OF THE TROUGH NEAR 10N78W. THE TROUGH WILL SLOWLY MOVE W THU THROUGH SUN WHILE GRADUALLY LOSING ITS IDENTITY INTO MON. THIS WILL ALLOW FOR THE N-NE WINDS OF 20-25 KT TO SHIFT WESTWARD TO ALONG THE COAST OF CENTRAL AMERICA BY THU...BUT DIMINISH LATE FRI THROUGH SUN AS THE GRADIENT SLACKENS. WAVEWATCH GUIDANCE INDICATES THAT 10 FT MAX SEAS IN THE FAR SW WATERS BUILD SLIGHTER HIGHER BY LATE THU INTO FRI...THEN DIMINISH TO 8 FT SAT...AND TO 5 FT SUN AND MON. THESE VALUES STILL LOOK REASONABLE GIVEN LARGE FETCH AREA AND LONG DURATION OF THE N-NE 20-25 KT WINDS...AND SO WILL CLOSELY FOLLOW THE GUIDANCE. BUOYS N OF THE AREA IN THE ATLC INDICATE THAT A SWELL TRAIN CONSISTING OF SEAS IN THE RANGE OF 8-11 FT WILL CONTINUE TO PROPAGATE S INTO THE TROPICAL N ATLC WATERS THROUGH LATE FRI NIGHT PER WAVEWATCH GUIDANCE...THEN SLOWLY SUBSIDE SAT THROUGH MON. SW N ATLC W OF 65W... FRONTAL TROUGH EXTENDS FROM 26N65W SW TO NEAR 21N68W EARLY THIS MORNING. THE FRONT...WHILE WEAKENING...WILL REMAIN THROUGH EARLY SAT UNDER UPPER LEVEL ZONAL FLOW THEN BEGIN TO SHIFT EASTWARD AS A COLD FRONT FRONT LEADING A STRONG AREA OF HIGH PRES THEN RAPIDLY MOVES SOUTHEASTWARD ACROSS THE NORTHERN AND EASTERN PORTIONS AS IT NEARS THE STATIONARY FRONT. MEANWHILE...MOST OF THE MODELS HINT AT POSSIBLE WEAK LOW PRES FORMING ALONG THE TROUGH ON FRI THEN QUICKLY MOVES NE TO THE E OF THE AREA SAT. OVER THE NORTHERN PORTION OF THE AREA E OF 73W HAVE DIMINISHED TO 15-20 KT...AND WILL DIMINISH FURTHER TO 10-15 KT THIS MORNING AS HIGH PRES SETTLES IN ACROSS THE AREA. E WINDS OF 10-15 KT OVER THE SOUTHERN PORTION OF THE AREA WILL INCREASE TO 15-20 KT TONIGHT BEFORE VEERING TO E-SE E OF THE BAHAMAS ON SUN. ELSEWHERE A TIGHT PRES GRADIENT WILL ALLOW FOR NE WINDS OF 20-25 KT TO THE N OF 24N AND OF THE FRONT TO NEAR 74W BEGINNING TONIGHT AND LASTING TO LATE FRI NIGHT BEFORE DIMINISHING TO NE 15-20 KT LATE SAT AND FURTHER ON SUN TO 10-15 KT AS THEY VEER AROUND TO THE E-SE AND TO S-SW AND INCREASING TO 20-25 KT LATE SUN AND MON. THIS WILL BE IN RESPONSE TO A STRONG COLD FRONT EXPECTED TO MOVE OFF THE SE U.S. COAST INTO THE NW WATERS POSSIBLY DURING SUN AFTERNOON...AND QUICKLY MOVE TO THE EASTERN PORTION MON. GALE FORCE WINDS ARE EXPECTED OVER PORTION OF THE NORTHERN WATERS BOTH E AND W OF THE FRONT ALONG WITH LARGE NW SWELLS BUILDING SEAS TO AS HIGH AS POSSIBLY 19 OR 20 FT ALONG THE NORTHERN BOUNDARY MON. N SWELLS OF UP TO 11 FT OVER THE EASTERN PORTION OF THE AREA SLOWLY SUBSIDE TO 9 FT BY FRI. WARNINGS... ATLC... .AMZ080...GALE CONDITIONS EXPECTED N OF 27N ON EITHER SIDE OF FRONT SUN AND N OF 27N E OF FRONT MON. CARIBBEAN... .NONE. GULF OF MEXICO... .GMZ086...GALE CONDITIONS EXPECTED N OF 27N SUN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE