000 AGXX40 KNHC 240712 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 310 AM EDT SAT APR 24 2010 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... HIGH PRESSURE HAS MOVED EAST OF THE GULF WITH A BROAD AREA OF RETURN FLOW GENERALLY W OF 85W. A 0352 UTC ASCAT PASS INDICATED AN AREA OF SE TO S WINDS OF 20 KT OVER THE GULF W OF 90W WHICH CORRELATED WELL WITH OBSERVATIONS FROM SURFACE PLATFORMS AS WELL. AS OF 06 UTC A COLD FRONT REMAINS OVER TEXAS AND HAS YET TO MOVE INTO THE GULF OF MEXICO. HOWEVER NWP MODELS ARE IN AGREEMENT IN THAT THE FRONT WILL BE IN THE GULF BETWEEN 09-12 UTC TIMEFRAME AND EXTENDS FROM SE LOUISIANA TO THE BAY OF CAMPECHE BY THIS EVENING. THEREAFTER THE FRONT WEAKENS CONSIDERABLY AND ALSO SLOWS DOWN AND BY LATE SUN EXTENDS FROM THE FL PANHANDLE TO THE YUCATAN PENINSULA AS NOTHING MORE THAN A FRONTAL TROUGH. THE TROUGH CONTINUES SE AND EXITS THE GULF MON NIGHT AS WEAK HIGH PRES BUILDS OVER THE GULF LATE MON INTO TUE. ANOTHER COLD FRONT MOVES INTO THE N-CENTRAL GULF TUE NIGHT AND CLIPS THE NE PORTION OF THE AREA WED WITH A REINFORCING HIGH PRES IN ITS WAKE. IN THE MEANTIME...THE TAIL END OF THE FRONTAL TROUGH STALLS OVER THE YUCATAN PENINSULA LATE MON AND TUE THEN MOVES INTO THE BAY OF CAMPECHE ON WED. LOWER PRESSURES IN THE AREA COUPLED WITH HIGH PRES BUILDING DOWN FROM THE SE U.S. MAINTAINS AN AREA OF LIGHT TO MODERATE E WINDS OVER MOST OF THE GULF ON WED. CARIBBEAN SEA AND TROPICAL N ATLC FROM 07N TO 22N W OF 55W...A FAIRLY TIGHT PRES GRADIENT EXISTS OVER THE CENTRAL AND W CARIBBEAN WITH A 0210 UTC ASCAT PASS INDICATING NE-E WINDS OF 20-25 KT NEAR THE COAST OF COLOMBIA. THESE WINDS WERE CONFIRMED BY A COUPLE OF SHIP REPORTS IN THE AREA. THE SAME ASCAT PASS MISSED THE AREA OF WINDS IN THE GULF OF HONDURAS. NONETHELESS THE OVERALL PATTERN PERSISTS INTO SUN AND SUN NIGHT. THEREAFTER NWP MODELS SHIFTS THE SEMI-PERMANENT AREA OF LOW PRES OVER COLOMBIA INTO THE SW CARIBBEAN SEA WITH ITS REMNANTS DEGENERATING INTO A TROUGH WHILE LOW PRES REDEVELOPS OVER COLOMBIA ON MON. TRADES WILL DIMINISH SLIGHTLY ACROSS THE MAJORITY OF THE CARIBBEAN SUN NIGHT THROUGH EARLY WED AS THE PRES GRADIENT WEAKENS...WITH 20 KT TRADES PERSISTING MAINLY S OF 13N E OF 75W. OTHERWISE EXPECT LONG PERIOD NE SWELLS OF UP TO 8 FT TO BLEED THROUGH THE NE ATLC PASSAGES MON INTO TUE. IN THE TROPICAL N ATLC...A SERIES OF WEAK FRONTAL TROUGHS WILL MOVE ACROSS THE NORTHERN PORTION OF THE BASIN THIS EVENING THROUGH THROUGH EARLY SUN WITH WINDS GENERALLY NE-E 10-15 KT ACROSS THE AREA. HIGH PRES BUILDS DOWN FROM THE NW-N LATER ON SUN AND TRADES WILL INCREASE TO 20 KT S OF 17N ON MON AND PERSISTING THROUGH WED AS THE PRES GRADIENT STRENGTHENS. IN ADDITION...LONG PERIOD NORTHERLY SWELL OF UP TO 12 FT WILL PROPAGATE THROUGH THE AREA SUN NIGHT THROUGH EARLY NEXT WEEK...WHILE EASTERLY SWELL ALSO BUILDS MAINLY S OF 17N AS THE TRADEWIND FETCH LENGTH INCREASES. SW N ATLANTIC S OF 31N W OF 65W... 1019 MB HIGH PRES CENTERED NEAR 28N75W WITH GENERALLY LIGHT WINDS IS BUILDING ACROSS MOST OF THE AREA CURRENTLY. A REINFORCING COLD FRONT WILL CLIP THE FAR NE PORTION LATER TODAY WITH NW WINDS PICKING UP TO 15-20 KT AND SEAS BUILDING 9-12 FT. THIS SAME SURGE IS EXPECTED TO PRODUCE GALES MUCH FURTHER E OVER THE HIGH SEAS FORECAST AREA TONIGHT. OTHERWISE HIGH PRES HOLDS IN PLACE OVER THE CENTRAL PORTION OF THE ZONE THROUGH TONIGHT WITH SOUTHERLY RETURN FLOW INCREASING ALONG THE FLORIDA COAST BEGINNING THIS EVENING AND CONTINUING THROUGH SUN EVENING. THE HIGH WILL SHIFT TO THE E AS THE NEXT COLD FRONT APPROACHES. THE FRONT WILL MOVE OFF OF N FLORIDA LATE MON SLOWLY MOVING TO THE E AND EXTENDING FROM 31N74W TO E-CENTRAL FLORIDA EARLY TUE...THEN WEAKENS TO FRONTAL TROUGH FROM 31N67W TO OFF THE CENTRAL BAHAMAS LATE TUE. A REINFORCING COLD FRONT WILL MOVE OFF THE GEORGIA/N FLORIDA COAST TUE NIGHT AND EXTEND FROM NEAR 31N67W TO JUST OFF THE CENTRAL BAHAMAS WED EVENING HAVING OVERTAKEN THE OLD FRONTAL TROUGH. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER COBB