000 AGXX40 KNHC 210718 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1215 PM EST FRI FEB 20 2009 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO... CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... SOUTHERLY RETURN FLOW IS ALREADY PICKING UP TO THE 20 KT RANGE IN THE WESTERN GULF OF MEXICO AHEAD OF THE COLD FRONT CURRENTLY DIVING THROUGH THE CENTRAL PLAINS. THIS BOUNDARY SHOULD MAKE ITS WAY OFF THE TX COAST INTO THE NW GULF SAT AFTERNOON...WITH WINDS TURNING NORTHERLY AND RANGING FROM 20 TO 30 KT BEHIND THE FRONT. CONFIDENCE HAS INCREASED IN THE PREVIOUS MIMATS FORECAST WHICH CALLED FOR WINDS TO NOT REACH GALE FORCE BEHIND THE RATHER PROGRESSIVE COLD FRONT. THE COLD FRONT IS EXPECTED TO DISSIPATE OVER THE WESTERN GULF BY SUN NIGHT WITH THE BOUNDARY LYING NEAR NAPLES FL AND GENERALLY ALONG 25N OVER THE EASTERN GULF...BUT WILL QUICKLY MOVE SOUTHEAST OF THE GULF ON MON. NORTHERLY FLOW AROUND 25 KT WILL FUNNEL THROUGH THE YUCATAN CHANNEL SUN EVENING AHEAD OF THE FRONT...WITH WINDS TURNING LIGHTER MON AS THE RIDGE AXIS SLOWLY MAKES ITS WAY EASTWARD ACROSS THE CENTRAL GULF INTO THE EASTERN GULF OF MEXICO TUE-THU. THE NEXT DEEP LAYER TROUGH WILL MOVE SOUTHWARD INTO THE SOUTHERN PLAINS TUE-THU...ALLOWING SOUTHERLY RETURN FLOW TO KICK UP ONCE AGAIN OVER THE WESTERN GULF. CARIBBEAN... THE PRESSURE GRADIENT BETWEEN THE LOW PRESSURE OVER COLOMBIA AND THE SUBTROPICAL RIDGE WILL BUILD OVER THE WEEKEND...ALLOWING WINDS TO GENERALLY FALL IN THE 20 TO 30 KT RANGE ACROSS MUCH OF THE CARIBBEAN E OF 80W. GALE CONDITIONS CAN BE FOUND NEAR THE COAST OF COLOMBIA AND ARE EXPECTED TO CONTINUE FOR AT LEAST THE NEXT 48 HOURS. THE 0244 UTC ASCAT PASS SHOWED WINDS JUST BELOW GALE FORCE...BUT KNOWING THE ASCAT RUNS LOW WINDS WINDS IN THIS RANGE...FEEL CONDITIONS WARRANT THE WARNING. BY SUN NIGHT...THE SUBTROPICAL HIGH WILL BEGIN A EASTWARD MIGRATION AS DEEP LAYER TROUGH SUPPORTING THE COLD FRONT MAKING ITS WAY THROUGH THE GULF OVER THE WEEKEND ENCOUNTERS THE RIDGE. WINDS SHOULD PICK UP OVER THE NW CARIBBEAN INCLUDING THE YUCATAN CHANNEL SUN EVENING INTO MON AS THE COLD FRONT PASSES THROUGH THE GULF AND MEETS UP WITH THE REMNANT TROUGH ASSOCIATED WITH THE DISSIPATING COLD FRONT CURRENTLY OVER NW WATERS. AS THE TROUGHING EDGES EASTWARD...THE PRESSURE GRADIENT WILL RELAX SOMEWHAT OVER THE CARIBBEAN...AND WINDS SHOULD BEGIN TO DIMINISH GENERALLY TO THE 15 TO 20 KT RANGE E OF 80W TUE-THU. ATLC... THE PERSISTENT SUBTROPICAL RIDGE IS FORCING THE DEEP LAYER TROUGH CURRENTLY OVER THE WESTERN ATLC NORTHEASTWARD OVER THE NW EDGE OF THE RIDGE. THE RIDGE IS EXPECTED TO MIGRATE WEST OVER THE WEEKEND...LIFTING THE SW EDGE OF THE WEAKENING COLD FRONT CURRENTLY OVER FORECAST WATERS FROM 31N65W TO THE CENTRAL BAHAMAS NORTHWARD WHILE THE LEADING EDGE CONTINUES EAST THROUGH THE HIGH SEAS FORECAST AREA. MEANWHILE...STRONG TRADE WINDS WILL CONTINUE SOUTH OF 20N. THE NEXT FRONT WILL PASS OFF THE NE FL COAST SUN...INCREASING WINDS TO AROUND 30 KT NEAR THE FRONT. THIS DEEP LAYER TROUGH WILL ALSO LOSE MUCH OF ITS PUNCH OVER FORECAST WATERS AS IT MOVES EASTWARD AND IS FORCED N OF THE SUBTROPICAL RIDGE. HOWEVER...THIS TROUGH WILL EAT INTO THE SURFACE RIDGING A BIT MORE THAN ITS PREDECESSOR...ALLOWING TRADES TO SUBSIDE SLIGHTLY OVER THE WESTERN PORTION OF THE ATLC S OF 20N TUE-THU. ATLANTIC... NONE. CARIBBEAN... GALE WARNING FROM 10N-13N BETWEEN 75W-77W...AMZ084. GULF OF MEXICO... NONE. FORECASTER SCHAUER CLARK. TROPICAL PREDICTION CENTER.