000 AGXX40 KNHC 181805 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST WED FEB 18 2009 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO... CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... COLD FRONT CURRENTLY OVER SE TEXAS IS EXPECTED TO MOVE INTO THE NW WATERS LATER THIS AFTERNOON OR EVENING. AHEAD OF THE FRONT SLY WINDS IN THE 15-20 KT RANGE COVER MUCH OF THE GULF... INCREASING TO 20 TO 25 KT OVER THE NE WATERS TONIGHT. WINDS WILL SHIFT TO THE NW AND INCREASE TO 20-25 KT N OF THE FRONT. THE BOUNDARY SWEEPS THROUGH THE ENTIRE GULF THROUGH THU NIGHT WITH WINDS/SEAS GRADUALLY SUBSIDING FRI AS HIGH PRES BUILDS ACROSS THE N GULF WATERS. THE HIGH SHIFTS OVER FLORIDA SAT NIGHT AS ANOTHER COLD FRONT ENTERS THE NW WATERS. GLOBAL MODELS ARE IN FAIR AGREEMENT FOR LONG RANGE IN SHOWING A FAIRLY SHARP UPPER TROUGH SUPPORTING THE SECOND FRONT. THIS...COMBINED WITH HIGH PRES SURGING S FROM CANADA MAY RESULT IN A GALE EVENT FOR THE WRN GULF...ESPECIALLY CONCERNED FOR FAVORED ZONE NEAR THE COAST OF MEXICO. FOR NOW...STAYED WITH 30 KT AS IS STILL FAIRLY LONG RANGE AND WAITING FOR MORE MODEL RUN-RUN CONSISTENCY. CARIBBEAN... HIGH PRES IS SHIFTING E OVER THE W ATLC CENTERED NEAR 30N75W. THE PRESSURE GRADIENT BETWEEN THIS HIGH AND LOWER PRES OVER S AMERICA IS PRODUCING 25-30 KT TRADES NEAR THE COAST OF COLOMBIA AND A LARGER SWATH OF 20-25 KT OVER MUCH OF THE AREA BETWEEN 67W AND 82W. THE HIGH WILL RETREAT INTO THE CENTRAL/EAST ATLC BY THU NIGHT AS A COLD FRONT MOVES INTO THE YUCATAN CHANNEL. THIS PATTERN WILL ALLOW TRADES TO WEAKEN. HOWEVER...THE FRONT QUICKLY DISSIPATES AND ANOTHER HIGH BUILDS OVER THE W ATLC THIS WEEKEND INCREASING TRADES AGAIN. LARGE NLY SWELL OF 11-13 SECONDS AND UP TO 10 FT SEA HEIGHTS ARE EXTENDING THROUGH MOST OF THE PASSAGES. THIS SWELL WILL CONTINUE TO AFFECT THE WINDWARD PASSAGE THROUGH FRI AND E CARIBBEAN PASSAGES THROUGH SAT. ATLANTIC W OF 55W... WINDS ARE DIMINISHING ACROSS MUCH OF THE ZONE AS THE LARGE AND POWERFUL LOW PRES SYSTEM CONTINUES TO TRACK NE ACROSS THE N ATLC. HOWEVER...LONG PERIOD NLY SWELL IS AFFECTING MUCH OF THE AREA ELEVATING SEAS UP TO 17 FT...HIGHEST OVER THE NE WATERS. AN ALTIMETER PASS FROM EARLIER TODAY REVEALED SEAS AS HIGH AS 22 FT JUST E OF THE ZONE. HOWEVER...AS ONE EVENT IS WINDING DOWN THE NEXT ONE IS STARTING UP. SCATTEROMETER DATA SHOWS SLY WINDS INCREASING TO 20 KT OVER THE NW WATERS AND THESE WINDS WILL CONTINUE TO INCREASE AS A COLD FRONT APPROACHES. SLY WINDS ARE EXPECTED TO REACH GALE FORCE THU MORNING-MIDDAY OFF THE NE FLORIDA COAST N OF 28N AND THEN SHIFT E WITH THE FRONT. GALES ARE EXPECTED TO DIMINISH IN THE AREA BY FRI MORNING AS THE FRONT LOSES UPPER SUPPORT. THE FRONT STALLS AND WEAKENS ACROSS THE SE PART OF THE AREA FRI AND SAT AND THEN ATTENTION TURNS BACK TO THE NW WATERS AS ANOTHER COLD FRONT APPROACHES. ATLANTIC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. FORECASTER CANGIALOSI. TROPICAL PREDICTION CENTER.