000 AGXX40 KNHC 120636 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 235 AM EDT WED MAR 12 2008 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... A WEAKENING COLD FRONT IS SLOWLY MAKING ITS WAY ACROSS THE GULF AND IS SLIGHTLY SLOWER THAN FCST AS IT EXTENDS FROM A 1013 MB SFC LOW SW OF APALACHICOLA TO BAY OF CAMPECHE. IN ITS WAKE A 1022 MB HIGH OVER E-CENTRAL TEXAS WITH A RIDGE DOWN THE E COAST OF MEXICO IS PROVIDING ENOUGH SUPPORT FOR 20 KT WINDS OVER THE BAY OF CAMPECHE. THE FRONT SHOULD CONTINUE MOVING SE AND CONTINUE TO WEAKEN AND EXTEND FROM EXTREME S FLORIDA TO NRN BAY OF CAMPECHE THIS EVENING. WEAK HIGH PRES BUILDING BEHIND THE FRONT MOVES E TODAY/THU AND E OF THE AREA THU NIGHT. THIS ALLOWS RETURN FLOW TO SPREAD OVER MOST OF THE GULF LATE THU AND FRI REACHING 15 TO 20 KT MOST AREAS W OF 85W...AND 20-25 KT N OF 25N ON SAT. THE CONVECTIVE FEEDBACK PROBLEM OF THE PAST SEVERAL GFS RUNS HAS BEEN RESOLVED WITH A MUCH MORE UNIFORM FIELD NOTED IN THE MODEL 10-M WINDS AND NWW3 SEAS LATE THU AND FRI. NEXT COLD FRONT EXPECTED TO MOVE OFF THE TEXAS COAST LATER SAT WHICH IS LATER THAN PREVIOUSLY FCST AND MORE IN LINE WITH THE UKMET/GFS ENSEMBLES. GIVEN THE BETTER PERFORMANCE OF THE UKMET/GFS ENSEMBLES WILL NOT BRING THE FRONT AS FAR S AS THE OPNL GFS AND KEEP FRONT EXTENDING FROM W-CENTRAL FLORIDA TO 27N97W BY LATE SUN. NLY WINDS QUICKLY VEER TO NE TO E BUT REMAIN 20 TO LOCALLY 25 KT N OF THE FRONT. SW N ATLC... A WEAK QUASI-STATIONARY FRONT EXTENDS FROM 28N65W TO THE NRN BAHAMAS WITH SLY FLOW ALREADY BRIDGING THE FRONT W OF 73W. THIS BOUNDARY...OR ITS REMNANTS...IS EXPECTED TO CONTINUE NWD AND MERGE WITH THE APPROACHING COLD FRONT FROM THE GULF LATER TODAY AND EXTEND FROM 31N71W TO THE NW BAHAMAS. SW WINDS OF 20-25 KT ARE EXPECTED N OF 26N E OF THE FRONT BUT MAINLY OVER AREAS E OF 70W. NW WINDS NEAR 20 KT ARE EXPECTED BRIEFLY W OF THE FRONT THEN DIMINISH SIGNIFICANTLY BY EARLY THU. THE FRONT MOVES E OF THE AREA ON THU EXCEPT FOR THE STALLED TAIL END EXTENDING FROM 27N65W TO 26N75W. HIGH PRES QUICKLY BUILDS E THU AND THU NIGHT THEN JUST E OF THE REGION BY FRI. THE INCREASE IN THE SLY RETURN FLOW IS DELAYED UNTIL SAT OVER THE FAR NW PORTION ON SAT IN ADVANCE OF A STORM SYSTEM OVER THE CENTRAL AND EASTERN U.S. THE ASSOCIATED COLD FRONT IS EXPECTED TO MOVE INTO THE AREA LATE SAT NIGHT AND EXTEND FROM 31N68W TO E-CENTRAL FLORIDA BY LATE SUN...AGAIN IN LINE WITH THE UKMET/GFS ENSEMBLES. UPPER TROUGH AMPLIFIES SUCH THAT THE FRONT MAY HAVE THE GREATEST IMPACT OVER THE N AND E WATERS E OF 70W WITH NW WINDS REACHING 20-25 KT...POSSIBLY 30 KT PER THE UKMET...THOUGH WILL NOT FCST THAT AT THIS TIME AND WAIT FOR ADDITIONAL MODEL RUNS. CARIBBEAN... THIS EVENINGS QSCAT PASS SHOWED AN AREA OF 25-30 KT NE WINDS NEAR THE COAST OF COLOMBIA...HIGHER THAN THE PREVIOUS SEVERAL DAYS AND NWP MODEL FCSTS. QSCAT ALSO SHOWED MAINLY 15-20 KT TRADES ELSEWHERE BETWEEN 70W-80W AND 10-15 KT OVER THE REMAINDER OF THE REGION. OVERALL...LITTLE CHANGES ARE EXPECTED UNTIL LATE AND SAT FRI WHEN SE FLOW DEVELOPS OVER THE NW PORTION IN RESPONSE TO A STORM SYSTEM AND FRONTAL BOUNDARY OVER THE CENTRAL AND EASTERN CONUS. BY SUN A SUPPRESSED RIDGE AHEAD OF THE E CONUS COLD FRONT KEEPS SUBNORMAL TRADES OVER MOST OF THE AREA WITH THE EXCEPTION OF THE FAR SW CARIBBEAN WHERE 20-25 KT WINDS REMAIN. WARNINGS... ATLANTIC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. FORECASTER COBB