000 AGXX40 KNHC 181910 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 310 PM EST THU MAR 18 2010 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... A BROAD RIDGE EXTENDING FROM NE TX TO THE FL STRAITS AND THE NW CARIB...WHILE A SECONDARY HIGH WAS LOCATED ACROSS THE SW GULF NEAR 21N97W. THE RIDGE WILL GRADUALLY BECOME ORIENTATED N TO S ALONG 94W THIS EVENING WITH THE PARENT SURFACE HIGH PRES FORMING OVER THE NW WATERS. THIS HIGH WILL SHIFT E ALONG 29-30N FRI TO A PSN OFF CAROLINA COASTS BY SUNRISE SAT WITH THE ASSOCIATED RIDGE DISSECTING THE GULF FROM NE TO SW. SE RETURN FLOW WILL BEGIN LATE TONIGHT OVER THE NW WATERS AS THE SURFACE HIGH DEVELOPS ALONG THE LOUISIANA COAST...AND INCREASING TO 15 TO 20 KT FRI. THE SE RETURN FLOW WILL SPREAD E COVERING ALL WATERS FRI NIGHT. THE NEXT COLD FRONT MOVES OFF THE TX COAST AROUND 00 UTC SUN. THIS FRONT WILL RACE SE TO THE FL STRAITS BEFORE MIDNIGHT SUN NIGHT. GUIDANCE STILL SUGGESTING A LARGE AREA OF NLY GALES ACROSS THE W HALF OF THE GULF...SO WILL CONTINUE MINIMAL GALE CONDITIONS FOR THE NW AND SW ZONES BEGINNING SAT EVENING INTO LATE SUN MORNING. PATTERN SEEMS PROGRESSIVE AGAIN AS POST FRONTAL HIGH PRES WILL RACE E ACROSS THE NORTHERN COASTAL PLAINS SETTING UP SE NW EARLY MON AND ALL WATERS BY MIDDAY TUE. TROPICAL ATLC AND CARIBBEAN SEA... A FRONTAL TROUGH EXTENDS FROM 21N55W TO 20N N OF THE N LEEWARDS...WITH THE W END BEGINNING TO DRIFT NW TODAY IN ADVANCE OF DEEPENING LOW OFF THE SE U.S. COAST. A BROAD INVERTED TROUGH OVER THE E CARIBBEAN ALONG 73/74W WITH CONTINUE THROUGH EARLY SAT THEN FILL AS ELY TRADES BUILD FROM THE E CARIB INTO THE CENTRAL AND W CENTRAL CARIB. WEAK FRONTAL ZONE/WIND SURGE MOVING SE ACROSS THE NW CARIB AND INTO NRN HONDURAS ATTM WILL CONTINUE SE AND REACH NEAR THE WINDWARD PASSAGE TO COAST NICARAGUA BY 12 UTC FRI. NLY FLOW BEHIND THIS FEATURE WILL CONTINUE TO DOMINATE THE CARIBBEAN W OF 75W THROUGH FRI...THEN ELY TRADES RESUME TILL A NEXT COLD FRONT ARRIVES YUCATAN CHANNEL AROUND SUNSET SUN. LARGE CLUSTER OF DEEP CNVTN ACROSS THE CENTRAL CARIB THIS MORNING HAS DIMINISHED TODAY...BUT GLOBAL MODELS SUGGESTING THIS CONVERGING LOW TO MID LEVEL MOISTURE ACROSS THE S CENTRAL CARIB WILL ADVECT N INTO HAITI NEXT 24 HOURS AND COULD BECOME TRAPPED JUST AHEAD OF APPROACHING FRONTAL ZONE...AND WITH JET DYNAMICS IN THE VICINITY...COULD SPELL PERIODS OF HEAVY RAINFALL FOR PORTIONS OF WRN HISPANIOLA...AND NAMELY HAITI...WHERE TENT COMMUNITIES COULD BE STRONGLY IMPACTED. SW N ATLC W OF 55W... LOW PRES HAS DEEPENED OFF THE GA/SC COASTS AND WAS MOVING NE...WITH A SERIES OF TROUGHS ROTATING AROUND THE PARENT MID LEVEL LOW. ONE LEADING FRONTAL TROUGH EXTENDED FROM SW OF BERMUDA ACROSS E CENTRAL CUBA. A BROAD ZONE OF 20-25 KT W-SW WINDS WAS OCCURRING N OF 25N BEHIND THIS BOUNDARY AND COMBINING WITH LONG PERIOD NE SWELL MOVING INTO FLORIDA AND THE ATLC W OF 68W TO PRODUCE SEAS AS HIGH AS 12 FT IN MERGING NE SWELL AND WLY WIND WAVES. THE LOW IS FORECAST TO MOVE VERY LITTLE IN THE NEXT 24 HOURS WITH S TO SW FLOW INCREASING E OF 70W AHEAD OF THE ASSOCIATED FRONT...AND THE BROAD ZONE OF 20-25 KT BEHIND THE FRONT LIFTING MOSTLY NE OF THE AREA. THIS LOW TO WEAKEN AND LINGER S OF 35N THROUGH SAT WITH SECONDARY SURGES TO FOLLOW THIS FRONT. ANOTHER COLD FRONT MOVES OFF GA COAST LATE SUN...REACHING FROM 31N70W TO CENTRAL BAHAMAS MON. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .GMZ080 AND GMZ082...GALE CONDITIONS EXPECTED EARLY SAT NIGHT INTO EARLY SUN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER STRIPLING