000 AGXX40 KNHC 271759 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 200 PM EDT WED MAR 27 2013 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... SHIP AND BUOY OBSERVATIONS CONFIRM WINDS AND SEAS ARE BELOW ADVISORY CONDITIONS FOR THE FIRST TIME SINCE THE FRONTAL PASSAGE AND ARE NOT EXPECTED TO REACH ADVISORY CRITERIA AGAIN THROUGH SUN. THE 1200 UTC GFS WAS USED TO UPDATE THE FORECAST. THE MODELS ARE IN GOOD AGREEMENT THROUGH THE WEEKEND. SW N ATLC S OF 31N W OF 55W... A COLD FRONT WAS ANALYZED FROM 31N50W TO THE WINDWARD PASSAGE THIS MORNING. SCATTERED SHOWERS CONTINUE TO BE FOUND NEAR THE FRONT. A STRONG SHORTWAVE SYSTEM PASSING BY BERMUDA IS ENHANCING WINDS WELL W OF THE COLD FRONT OVER WATERS N OF 26N BETWEEN 60W- 70W. THE 1438 UTC ASCAT PASS SHOWS STRONG NW WINDS HERE. THE 0910 UTC JASON-1 PASS SHOWED SEAS IN THE 9-12 FT RANGE N OF 26N BETWEEN 72W AND 76W THIS MORNING. THE 1200 UTC ATMOSPHERIC AND OCEAN WAVE MODELS ARE REASONABLY WELL INITIALIZED COMPARED TO THESE OBSERVATIONS. WINDS AND SEAS OVER WESTERN WATERS WILL GRADUALLY DIMINISH/SUBSIDE TODAY THROUGH FRI WHILE MODERATE TO STRONG NW WINDS AND HIGHER SEAS WILL PREVAIL OVER NE WATERS TODAY THROUGH SAT AS A SERIES OF MID- TO UPPER-LEVEL IMPULSES ROTATE THROUGH THE MEAN TROUGH OVER THE WESTERN ATLC. ON SAT....HIGH PRES MOVES EAST-SOUTHEASTWARD OVER N WATERS. THIS WILL TAME THE WINDS AND SEAS THERE BUT INCREASE THE TRADES S OF 22N. BY SUN...A TROUGH NW OF THE AREA WILL INCREASE THE PRES GRADIENT BETWEEN IT AND THE HIGH ALLOWING FOR SOUTHERLY WINDS TO INCREASE OVER NW WATERS. THE MODELS ARE IN REASONABLE AGREEMENT ON THIS FORECAST SCENARIO. THE 1200 UTC GFS WAS USED TO UPDATE THE FORECAST. CARIBBEAN SEA AND TROPICAL N ATLC S OF 22N W OF 55W... A WEAKENING COLD FRONT EXTENDED FROM THE WINDWARD PASSAGE TO EASTERN HONDURAS THIS MORNING AND WILL MOVE SLOWLY SE BEFORE DISSIPATING OVER THE CARIBBEAN THU. RECENT BUOY OBSERVATIONS AND THE 0500 UTC OSCAT PASS AND THE 1440 UTC ASCAT PASS CONFIRM FRESH TO STRONG N WINDS LIE N OF THE FRONT...BUT THE TEMPERATURE CONTRAST IS WANING ACROSS THE BOUNDARY. THE 1200 UTC UKMET IS APPROXIMATELY 5 KT TOO WEAK WITH WINDS BEHIND THE FRONT...WITH THE 1200 UTC GFS APPEARING TO HAVE A GOOD HANDLE ON THE INITIAL CONDITIONS. BUOY 42057 HAS BEEN REPORTING 9-10 FT SEAS SINCE 1200 UTC THIS MORNING. THE 1200 MWW3 AND UKMET WAVE ALONG WITH THE 0000 UTC EC WAVE WERE ALL 1-3 FT LOWER THAN THE BUOY HERE...SO ADJUSTMENTS WERE MADE TOWARD THE OBSERVATION. FRESH TO STRONG TRADES WILL BUILD IN THE WINDWARD PASSAGE TONIGHT BEHIND THE FRONT AS WELL AS IN THE MONA PASSAGE AND ALONG THE S COAST OF HISPANIOLA ON FRI. THE MODELS ARE TYPICALLY UNDERDONE IN THE WINDWARD PASSAGE UNDER SUCH NE FLOW REGIMES...SO BUMPED UP THE WINDS AND SEAS A NOTCH THERE TONIGHT THROUGH SAT MORNING. TRADES WILL ALSO BUILD ALONG THE COAST OF COLOMBIA AS HIGH PRES N OF THE AREA MOVES IN BEHIND THE FRONT FRI INTO THE WEEKEND. THE GFS IS GENERALLY STRONGER WITH WINDS IN THE CENTRAL CARIBBEAN UNDER STRONG HIGH PRESSURE THAN THE OTHER MODELS AND TYPICALLY AGREES BEST WITH OBSERVATIONS. USED THE GFS TO ADJUST THE FORECAST WHICH SHOULD ALLOW FOR NEAR GALE CONDITIONS ALONG THE IMMEDIATE COAST OF COLOMBIA IN THE EARLY MORNING HOURS OVER THE WEEKEND. WARNINGS... GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .NONE. SW N ATLC... .NONE. EFFECTIVE 20 MARCH 2013...TAFB GRIDDED MARINE FORECASTS FOR 10-M WINDS...10-M WIND GUSTS...SIGNIFICANT WAVE HEIGHTS AND HAZARDS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) ON AN EXPERIMENTAL BASIS AT: HTTP://PREVIEW.WEATHER.GOV/GRAPHICAL ADDITIONAL INFORMATION IS AVAILABLE AT WWW.NWS.NOAA.GOV/OM/NOTIFICATION/PNS13OFFSHORE_HIGHSEAS.HTM NOTE...GRIDDED MARINE FORECASTS AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE WILL BE DISCONTINUED ONCE THE "OCEANIC" VIEW IS ADDED TO THE EXPERIMENTAL NDFD GRAPHICAL INTERFACE. $$ FORECASTER SCHAUER