000 AGXX40 KNHC 281758 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 200 PM EDT THU MAR 28 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... HIGH PRES SHIFTING FROM N OF THE AREA THROUGH NE WATERS THEN E OF THE AREA WILL DOMINATE THE FLOW REGIME THROUGH MON. WINDS AND SEAS WILL REMAIN BELOW ADVISORY CRITERIA. THE 1200 UTC GFS WAS USED TO UPDATE THE FORECAST. THE MODELS ARE IN GOOD AGREEMENT THROUGH THE WEEKEND. THE MODELS ARE IN REASONABLE AGREEMENT ON THE NEXT COLD FRONT APPROACHING THE NORTHERN GULF COAST ON TUE. SW N ATLC S OF 31N W OF 55W... A COLD FRONT WAS ANALYZED FROM 31N42W TO THE DOMINICAN REPUBLIC THIS MORNING. SCATTERED SHOWERS NEAR THE FRONT ARE EVIDENT ON THE SAN JUAN RADAR. BUOYS 41002 AND 41047 SHOWED SEAS 1-3 FT HIGHER THAN THE MWW3 WHICH APPEARS TO BE TOO FAST SUBSIDING SEAS. ADJUSTMENTS WERE MADE TO THE FORECAST ACCORDINGLY. WINDS AND SEAS OVER WESTERN WATERS WILL CONTINUE TO 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. AS EXPECTED...THE 1416 UTC ASCAT PASS SHOWS A NEW ROUND OF FRESH TO STRONG W-NW WINDS MOVING INTO THE AREA N OF 30N BETWEEN 60W-75W. OVER THE WEEKEND AND INTO MON.... HIGH PRES MOVES EASTWARD OVER N WATERS ALONG 29N. THIS WILL TAME THE WINDS AND SEAS IN N WATERS 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. THIS SHOULD BE TEMPORARY AS THE TROUGH IS EXPECTED TO LIFT NORTHWARD MON WITHOUT MOVING INTO THE AREA. 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 SHEAR AXIS EXTENDED FROM HAITI TO 12N OFF THE NICARAGUAN COAST THIS MORNING. IT WILL DISSIPATE BY TONIGHT. THE 1420 UTC ASCAT PASS SHOWS FRESH TO STRONG NE WINDS IN THE WINDWARD PASSAGE BEHIND THE SHEAR AXIS. 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 SUN MORNING. FRESH NE WINDS WILL MOVE INTO THE MONA PASSAGE AND ALONG THE S COAST OF HISPANIOLA ON FRI AND TRADES WILL 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 AND INTO MON MORNING. 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