000 AGXX40 KNHC 181746 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 145 PM EDT TUE MAR 18 2008 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO...LATEST OB FROM BUOY 42002 SHOWS 33 KT. ELSEWHERE BUOYS...SHIPS...AND SCATTEROMETER DATA OVER THE GULF SHOW STEADY 30 KT SE FLOW OVER MUCH OF AREA AHEAD OF A COLD FRONT ADVANCING THROUGH TEXAS. THIS IS THE RESULT OF A TIGHT PRESSURE GRADIENT BETWEEN A DEEP 996 MB LOW PRESSURE CENTER OVER NRN MEXICO...AND 1033 MB HIGH PRES OVER THE CAROLINA COAST. THE LOW WILL TRACK NE INTO THE TENNESSEE VALLEY BY LATE TOMORROW ALONG WITH ITS SUPPORTING UPPER TROUGH. FOR THE SHORT TERM...THE MAIN FORECAST ISSUE CONTINUES TO BE POTENTIAL FOR GALE FORCE SLY WINDS OVER THE WESTERN GULF. GIVEN THAT THE SEA SURFACE TEMPS OVER THE FAR NW GULF ARE IN THE LOWER TO MID 60'S...THE BOUNDARY LAYER WILL REMAIN FAIRLY STABLE WITH WARM SLY FLOW...AND INHIBIT GALES. FURTHER W...A TONGUE OF LOOP CURRENT WATER IN THE LOWER TO MID 70S REACHES NEAR THE MISSISSIPPI DELTA. WILL HOLD ON TO GALE WARNING FOR THE SMALL AREA OF THE N CENTRAL GULF...EVEN THOUGH IT'S MARGINAL. MEANWHILE SURFACE HIGH PRES WILL BUILD BEHIND THE LOW AND SHIFT THROUGH THE SOUTHERN ROCKIES INTO THE CENTRAL PLAINS WED. THIS OPENS THE DOOR TO A GALE POTENTIAL BEHIND THE FRONT OVER THE WESTERN GULF...CONSIDERING AN ENHANCED GRADIENT ALONG THE HIGH MEXICAN COASTAL TERRAIN. ADD IN DECENT CAA FROM THE FRONT OVER WATER TEMPS IN THE MID TO UPPER 70S...AND GALES LOOK LIKE A GOOD BET AT LEAST OVER THE SW GULF. IN FACT...IT LOOKS LIKE A STRONG REINFORCING SHOT OF COLD AIR FOLLOWS THE INITIAL FRONT. WILL EXPAND THE GALE AREA N TO MESH WITH COASTAL FORECASTS IN S TEXAS. LOOKING AHEAD...WINDS AND SEAS WILL DIMINISH FROM THU INTO THE WEEKEND. LONGER RANGE MODELS SHOW A WEAK FRONT EMERGING OFF THE NRN GULF COAST SUN...WITH SOME INCREASE IN NLY FLOW. CARIBBEAN AND TROPICAL N ATLC...A QUIKSCAT PASS FROM THIS MORNING SHOWS GALE FORCE CONDITIONS OFF THE COLOMBIAN COAST. SHIP AND SCATTEROMETER SHOW 30 KT OVER MUCH OF THE CENTRAL CARIBBEAN INCLUDING THE WINDWARD PASSAGE...AS A COLD FRONT DIPS INTO THE FAR NRN CARIBBEAN WATERS. THIS WILL LIKELY PERSIST AS HIGH PRES SHIFTS N OF THE AREA. THE OTHER ISSUE WILL BE LARGE...LONG PERIOD SWELL PUSHING INTO THE EASTERN CARIBBEAN AND TROPICAL N ATLC FROM WED THROUGH FRI. WINDS AND SEAS DIMINISH TOWARD THE WEEKEND AS THE HIGH PRES WEAKENS AND SHIFTS E...AND THE LARGE SWELL DECAYS. SW N ATLC...HIGH PRES IS BUILDING BETWEEN THE CAROLINAS AND BERMUDA BEHIND A COLD FRONT THAT MOVED S OF THE BAHAMAS YESTERDAY. WINDS ARE DIMINISHING AS THE HIGH BUILDS INTO THE AREA...BUT LARGE LONG PERIOD SWELL CONTINUES TO PUSH S. SLY WINDS WILL INCREASE TOMORROW OVER WATERS W OF N FLORIDA AHEAD OF A COLD FRONT EXPECTED TO MOVE OFF THE COAST EARLY THURSDAY. WARNINGS... ATLANTIC... NONE. CARIBBEAN... GALE WARNING ALONG COLOMBIAN COAST...AMZ084-086. GULF OF MEXICO... GALE WARNING GMZ080-082-084. FORECASTER CHRISTENSEN