000 AGXX40 KNHC 100539 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 140 AM EDT SUN AUG 10 2008 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... TODAY THROUGH MON NIGHT...THE UNUSUAL FRONT FOR THIS TIME OF YEAR HAS STALLED FROM THE BIG BEND AREA OF FLORIDA TO SE LOUISIANA AND IS QUICKLY FALLING APART...BUT IT DID ADVECT DRIER AIR BEHIND IT AND SOME GUSTY WINDS FOR A SHORT TIME. WINDS ARE LIGHT ACROSS MOST OF THE GULF TONIGHT...ESPECIALLY ALONG THE RIDGE AXIS WHICH LIES ALONG 25N. SHIPS/BUOYS AND EARLIER QSCAT DATA INDICATES 15 KT SLY RETURN FLOW OVER THE FAR W WATERS. THESE WINDS MAY EXPAND E AND INCREASE TO 20 KT BEGINNING SUN NIGHT AS LOW PRES TAKES SHAPE OVER THE S CENTRAL PLAINS...BUILDING SEAS TO 4-6 FT OVER THE FAR W WATERS. WINDS SHOULD REMAIN LIGHT OVER MUCH OF THE MIDDLE AND EAST ZONES...KEEPING SEAS IN THE 1-3 FT RANGE. TUE THROUGH THU...MUCH OF THE MODEL GUIDANCE IS SUGGESTING LOW PRES TRACKING E ACROSS THE SOUTHERN STATES ALONG A STATIONARY FRONT. THE TIGHTENED PRESSURE GRADIENT BETWEEN THE RIDGE AXIS ALONG 25N AND THE LOWS SHOULD SUPPORT SW TO W 20 KT WINDS OVER N PORTION OF THE WEST WATERS TUE AND THE N PORTION OF THE MIDDLE AND EAST ZONES WED. BY THU...LOW PRES SHIFTS OFFSHORE WITH WINDS RELAXING. OF NOTE...CURRENT WIND FORECAST IS MUCH LOWER THAN THE GFS WHICH SHOWS A SMALL AREA OF WINDS TO 30 KT OVER THE NE WATERS WED. SW N ATLC... TONIGHT THROUGH MON NIGHT...WEAK FRONT EXTENDS FROM 31N75W TO NE FLORIDA WITH SATELLITE IMAGERY AND A QSCAT PASS SHOWING EVIDENCE OF A WEAK FRONTAL LOW NEAR 30N77W. WINDS ARE VERY LIGHT NEAR THE LOW/FRONT BUT REMAIN 15-20 KT E OF THE FRONT N OF 28N OR SO. THE FRONT IS EXPECTED TO FIZZLE THROUGH EARLY MON WITH RIDGING BECOMING BETTER ESTABLISHED FROM 27N65W TO THE FLORIDA STRAITS. TUE THROUGH THU...MAIN FORECAST ISSUE WILL BE AN AREA OF LOW PRES THAT WILL TRACK E OFF THE CAROLINA COAST AND INCREASE SW/W WINDS OVER THE NRN WATERS WED AND THU. GFS CONTINUES TO SHOW WINDS OF 30 KT OVER THE FAR N WATERS...BUT IT REMAINS THE MOST AGGRESSIVE OF THE ALL GUIDANCE. HOWEVER...THE LARGE SCALE PATTERN LOOKS SIMILAR IN THE ECMWF AND UKMET SO MAY NEED TO TREND CLOSER TOWARD THE GFS SOLUTION IF MODELS SHOWS CONSISTENCY. CARIBBEAN... TONIGHT THROUGH MON NIGHT...ELY TRADES REMAIN STRONGEST IN THE TYPICALLY ENHANCED ZONE OVER THE S CENTRAL PORTION BETWEEN SEMI-PERMANENT LOW PRES OVER SOUTH AMERICA AND A 1028 MB HIGH CENTERED NEAR 33N45W. WINDS ARE VERY LIGHT OVER THE FAR NW CARIBBEAN DUE TO THE WEAKENED PRES PATTERN CAUSED BY THE FRONT IN THE GULF OF MEXICO. ELSEWHERE...TYPICAL MODERATE TO FRESH TRADES PREVAIL. WINDS ARE EXPECTED TO BECOME MORE UNIFORM ACROSS THE REGION BY MON AS THE FRONT DISSIPATES IN THE GULF...BUT OTHERWISE LITTLE SIGNIFICANT CHANGE IS EXPECTED. TUE THROUGH THU...MODEL GUIDANCE SHOWS THE TRADES SLACKENING DURING THIS TIME AS ATLC RIDGING WEAKENS AND SHIFTS NE SLIGHTLY. GFS IS DEVELOPING THE TROPICAL WAVE NEAR 26W AND TRACKS IT TOWARD THE TROP N ATLC ZONE LATE IN THE WEEK. ECMWF SHOWS SOME DEVELOPMENT TO THE WAVE FARTHER W NEAR 42W AND MOVES A WEAK SYSTEM INTO THE REGION BY MID-WEEK. WHILE BOTH OF THESE WAVES ARE SHOWING SOME ORGANIZATION...ITS TOO EARLY TO HAVE MUCH CONFIDENCE IN EITHER OF THESE SOLUTIONS...SO WILL CONTINUE TO MONITOR. WARNINGS... ATLANTIC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. .FORECASTER CANGIALOSI. TROPICAL PREDICTION CENTER.