000 AGXX40 KNHC 271731 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1230 PM EST THU NOV 27 2008 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO... CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. RADIOFAX SCHEDULE FOR GRAPHICAL WIND WAVE...SURFACE FORECAST AND PEAK WAVE PERIOD CHARTS HAS CHANGED. FOR THE ATLANTIC BASIN THIS INCLUDES 24...36...48 AND 72 HOUR WIND WAVE..24...48..72 HOUR SURFACE FORECAST AND 48 AND 72 HOUR PEAK WAVE PERIOD CHARTS. FOR ADDITIONAL INFORMATION PLEASE REFER TO THE FAX SCHEDULE ON THE NHC WEB SITE AT HTTP://WWW.NHC.NOAA.GOV/RADIOFAX.SHTML GULF OF MEXICO... HIGH PRES OF 1023 MB HAS BECOME CENTERED NEAR 28N85W THIS MORNING WITH A RIDGE SW TO THE NW YUCATAN PENINSULA...AND IS PROVIDING FAIRLY LIGHT WINDS AND LOW SEA THROUGHOUT THE GULF. WINDS ARE SLY IN THE 10-15 KT RANGE EXCEPT VARIABLE 5-10 KT IN THE NE PART...WHILE SEAS ARE IN THE 2-4 FT RANGE WITH A MAXIMUM OF 4 FT NEAR THE CENTRAL TEXAS COAST. WINDS WILL INCREASE OVER THE WESTERN IN RETURN SLY FLOW BEGINNING TONIGHT IN ADVANCE OF THE NEXT FRONTAL SYSTEM. LATEST GLOBAL MODEL GUIDANCE SUGGEST THAT THE COLD FRONT WILL MOVE INTO THE TEXAS COASTAL WATERS SAT MORNING...THEN SLOWLY REACH FROM S CENTRAL LOUISIANA TO S TEXAS BY SAT AFTERNOON BEFORE UPPER LEVEL SUPPORT IN THE FORM OF A STRONG UPPER TROUGH DEPICTED IN THE UPPER LEVEL FIELDS OF THE GLOBAL MODELS REINFORCES THE FRONT AND PUSHES IT FURTHER SE SUN AND MON AT A MUCH RAPID SPEED. INITIALLY... IT STILL APPEARS THAT WINDS MAY BE N IN 15-20 KT RANGE BEHIND THE FRONT...BUT QUICKLY BECOME STRONGER FROM THE NW IN THE 20-25 KT RANGE SUN AND MON...THEN DIMINISHING TO 15-20 KT TUE AFTER FRONT EXITS THE GULF MON. LATEST WAVEWATCH GUIDANCE SHOWS SEAS BUILDING UP TO 12 FT BEHIND THE FRONT WITH SEAS UP 10 FT WITHIN ABOUT 90-100 NM E OF THE FRONT ON SUN. CAN'T RULE A BRIEF INSTANCE OF WINDS REACHING TO GALE FORCE IN THE SW GULF ON SUN PARTICULARLY OVER THE FAR WESTERN PORTION IN POUNCED OFF GRADIENT BETWEEN THE FRONT AND MEXICO. ALSO...WINDS MAY POSSIBLY REACH 30 KT BEHIND THE FRONT OVER THE MIDDLE AND EASTERN GULF SUN AND MON BEFORE THEY DECREASE TUE. WILL CLOSELY MONITOR THE EVOLUTION OF THE MID-UPPER PATTERN AS TO HOW IT COMES INTO SYNC WITH DEVELOPMENT OF STRONG WINDS ASSOCIATED WITH THE FRONT AND MAKE ANY ADJUSTMENTS AS NECESSARY BASED ON THE LATEST MODEL GUIDANCE DURING THE NEXT 24-36 HOURS. CARIBBEAN SEA AND TROPICAL NORTH ATLANTIC OCEAN... THE OVERALL PRES GRADIENT THROUGHOUT THE AREA IS MUCH WEAKER THAN OBSERVED OVER THE PAST FEW DAYS WITH WINDS AND SEAS ALSO AT MUCH LOWER LEVELS. MAIN PROBLEM APPEARS TO BE LONG PERIOD N SWELLS OF UP TO 11 FT AFFECTING THE TROPICAL N ATLC N OF 14N. THESE HEIGHTS ARE IN PRETTY CLOSE AGREEMENT WITH LATEST WAVEWATCH GUIDANCE SO WILL FOLLOW GUIDANCE CLOSELY THROUGH FORECAST PERIOD. THESE SWELLS ORIGINATED FROM A PREVIOUS CENTRAL ATLC STORM SYSTEM WHICH HAS SINCE WEAKENED. HOWEVER...THE SWELLS WILL ONLY SLOW SUBSIDE TO 8-9 FT MON AND TUE. THE GULF OF MEXICO COLD FRONT MENTIONED ABOVE IS FORECAST TO ENTER THE NW WATERS MON MORNING. UNTIL THEN...WINDS AND SEAS WILL BE RATHER LIGHT OVER JUST ABOUT ALL ZONES IN THE FORECAST AREA...EXCEPT PRESENTLY IN THE NW CARIBBEAN WINDS ARE NE 15-20 KT N OF 15N E OF 82W BUT WILL DIMINISH TO 10-15 KT TONIGHT. BEHIND THE FRONT WINDS WILL INCREASE TO NW 20-25 KT MON. THE FRONT WILL THEN REACH A PSN FROM E CUBA TO NE NICARAGUA LATE MON ...AND FROM NEAR THE WINDWARD PASSAGE TO FAR SW CARIBBEAN SEA ON TUE AFTERNOON. WINDS WILL WEAKEN BEHIND THE FRONT OVER THE NW PORTION OF THE NW CARIBBEAN SEA TUE AS HIGH PRES SETTLES IN OVER THE E GULF OF MEXICO. WINDS SHOULD REMAIN N 20-25 KT WITH 25-30 KT WINDS NEAR THE COAST OF HONDURAS AND NORTHERN COSTA RICA ON TUE IN TIGHT GRADIENT SQUEEZE MUCH LIKE WHAT WAS OBSERVED DURING THE PAST FRONTAL EVENT THAT OCCURRED ABOUT 2 WEEKS WHERE 30 KT WINDS WERE NOTICED OVER PORTIONS OF THE NW AND SW CARIBBEAN SEA. EXPECT SEAS TO BUILD UP TO 11 FT BEHIND THE FRONT IN THE SW SECTION OF THE SEA TUE...AND TO 8 OR 9 FT IN THE NW SECTION. ELSEWHERE ACROSS THE CARIBBEAN SEA...TRADES WILL BE LIGHT THROUGH TUE (IN ABOUT THE 10-15 KT RANGE) WITH SEAS GENERALLY 3-5 FT EXCEPT 5-6 FT IN THE EASTERN CARIBBEAN ACROSS MUCH OF THE W CARIBBEAN AS HIGH PRES N OF THE AREA RETREATS EASTWARD IN ADVANCE OF THE COLD FRONT PORTION THAT MOVES ACROSS THE WESTERN ATLC. SW N ATLC... A COLD FRONT IS WEAKENING FROM 31N62W TO NEAR THE SE BAHAMAS WITH WINDS NOW LIGHT NW-N 5-10 KT NEAR THE FRONT AND SEAS 4-6 FT IN N SWELL AS REPORTED BY BUOY DATA NOT TOO FAR AWAY FROM THE FRONT. LONG PERIOD N SWELLS OF 7-9 FT CONTINUE OVER THE AREA E OF 70W...AND WILL SLOWLY DIMINISH TO 5-8 FT BY FRI NIGHT...AND FURTHER OVER THE FAR SE WATERS SAT THROUGH TUE OUTSIDE OF COLD FRONT AFFECTED WATERS MENTIONED BELOW. WEAK HIGH PRES SETTLING IN OVER THE AREA WILL BEGIN TO SHIFT E FRI NIGHT INTO SAT AS THE GULF OF MEXICO COLD FRONT DESCRIBED ABOVE MAKES EASTWARD PROGRESS THROUGH THE NW PORTION OF THESE WATERS LATE SUN INTO EARLY MON MORNING AS SEEN IN THE 12 UTC RUN OF THE GLOBAL MODELS AND THE 12 UTC RUN OF THE NAM. ALL GUIDANCE IS IN PRETTY GOOD AGREEMENT THAT WINDS ASSOCIATED WITH THE COLD FRONT WILL BE STRONG BOTH E AND W OF IT. AM PLANNING ON KEEPING THE 20-30 KT S-SW WINDS AHEAD OF THE FRONT N OF 26N AS INTRODUCED INT THE MORNING 1030 AM EST FORECAST UPDATE. BOTH GFS AND NOGAPS RUNS MAY BE ON THE HIGH SIDE AT THIS TIME WITH SW 30-40 KT E OF FRONT SUN NIGHT AND MON OVER THE FAR NW FORECAST WATERS...BUT WILL CLOSELY MONITOR EVOLUTION OF THE UPPER LEVEL MENTIONED ABOVE UNDER GULF OF MEXICO AS WELL AS UPDATED MODEL GUIDANCE FOR MENTIONING OF POSSIBLE GALE CONDITIONS IN FUTURE FORECAST PACKAGES. NEVERTHELESS...THERE MAY BE A VERY BRIEF PERIOD OF WINDS GUSTING IN EXCESS OF 30 KT AHEAD OF THE FRONT EARLY MON N OF ABOUT 28N AND W OF 76W. WINDS BEHIND THE FRONT SHOULD REACH TO 20-30 KT ON MON MORNING...AND MAYBE EARLY AFTERNOON WITH THE STRONGEST OF THE WINDS WITHIN ABOUT 300 NM W OF THE FRONT AND N OF 30N. THE FRONT IS EXPECTED TO EXTEND FROM 31N74W TO CENTRAL CUBA BY MON EVENING...AND FROM 31N65W TO NEAR HAITI BY LATE ON TUE WITH NW WINDS BEHIND DOWN TO MOSTLY NW 20 KT. SEAS WILL BE ON THE HIGH SIDE WITH MAXIMUM SEAS 10-16 FT W OF THE FRONT N AND NE OF THE BAHAMAS ON MON AND TUE. ATLANTIC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. FORECASTER AGUIRRE. TROPICAL PREDICTION CENTER.