000 AGXX40 KNHC 131753 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 153 PM EDT SUN MAY 13 2012 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... A WEAK FRONTAL BOUNDARY EXTENDING FROM SE LOUISIANA TO NE MEXICO HAS STALLED AS AN UPPER TROUGH CONTINUES TO LIFT OUT THROUGH THE LOWER MISSISSIPPI VALLEY TOWARD THE CAROLINAS. THE FRONT WILL WEAKEN WHILE VERY SLOWLY ATTEMPTING TO PROGRESS EASTWARD AS THE UPPER SUPPORT CONTINUES TO LIFT OFF TO THE NE. WEAK FORCING ASSOCIATED WITH THE UPPER TROUGH...AND UNSTABLE BOUNDARY LAYER CONDITIONS NEAR THE WARMER WATER OF THE NORTHERN EXTENT OF THE LOOP CURRENT ARE TOGETHER ALLOWING LINGERING SCATTERED CONVECTION OVER THE N CENTRAL AND NE GULF. THIS WILL DIMINISH AS THE UPPER TROUGHING CONTINUES TO LIFT OUT. THE FRONT WILL INCH EASTWARD THROUGH THE WEEK AND IT IS FORECAST TO EVENTUALLY DISSIPATE IN THE E GULF BY THU INTO FRI. A SURFACE RIDGE WILL BUILD ACROSS THE NORTHERN GULF ALONG 28N IN THE WAKE OF THE WEAK FRONTAL BOUNDARY. FURTHER SOUTH...UPPER FORCING ASSOCIATED WITH THE RIGHT-REAR ENTRANCE REGION OF THE SOUTHERN STREAM JET IS FOSTERING A CLUSTER OF STRONGER CONVECTION OFF THE MEXICAN COAST AND ALSO IN THE SW GULF S OF 26N...ON THE WEST SIDE OF A BROAD AND PERSISTENT SURFACE TROUGH WHICH EXTENDS FROM 25.5N95.5W TO 18.5N93.5W OVER THE BAY OF CAMPECHE. THE TROUGH WILL MOVE LITTLE OVER THE NEXT COUPLE OF DAYS BEFORE BECOMING DIFFUSE BY TUE. OTHERWISE...THE WEAK PRES PATTERN WILL MAINTAIN LIGHT TO MODERATE WINDS AND SEAS THROUGH THE WEEK. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... AN UPPER LEVEL TROUGH EXTENDS FROM 22N61W SOUTHWARD ACROSS THE ANEGADA PASSAGE TO NEAR LAKE MARACAIBO. THE TROUGH IS SLOWLY DRIFTING E AND ALTHOUGH CONVECTION FROM YESTERDAY HAS LARGELY DISSIPATED FROM HISPANIOLA TO THE LEEWARD ISLANDS...WEATHER WILL REMAIN UNSETTLED IN THIS AREA THROUGH TONIGHT...BEFORE THE TROUGH DAMPENS OUT AND SHIFTS FURTHER EAST INTO THE ATLANTIC. THE MAIN WEATHER IMPACT THROUGH THU WILL BE FRESH TO STRONG EASTERLY WINDS FROM THE TROPICAL N ATLC WATERS E OF THE WINDWARDS AND ACROSS THE CARIBBEAN TO NEAR 81W/82W...AS PERSISTENT HIGH PRES WELL N OF THE REGION WILL MAINTAIN THE ENHANCED EASTERLY FLOW. SEAS WILL BUILD TO UP TO 12 FT NW OF THE COAST OF COLOMBIA SUN THROUGH MON WITH THE PERSISTENT EASTERLY FETCH. FURTHER WEST...LOCAL WINDS OVER THE GULF OF HONDURAS WILL OCCASIONALLY REACH 20 KT...MAINLY DURING OVERNIGHT HOURS. OTHERWISE...LIGHT TO MODERATE E WINDS WILL PERSIST OVER THE FAR NW CARIBBEAN THROUGH THE WEEK. SOUTHWEST NORTH ATLC S OF 31N W OF 55W... A WEAK COLD FRONT EXTENDS FROM 31N58W TO 30N60W...THEN IS STATIONARY TO 27N63W CONTINUING AS A SHEAR LINE TO 25N72W. HIGH PRES BETWEEN THE CAROLINAS AND BERMUDA IS PROMOTING FRESH NE FLOW N OF 26N THROUGH THE NORTHERN BAHAMAS AND INTO EASTERN FLORIDA. THE SHEAR LINE WILL BECOME DIFFUSE AND THESE WINDS WILL GRADUALLY DIMINISH THROUGH TONIGHT AS THE HIGH MOVES INTO THE N CENTRAL ATLC AHEAD OF A DEEP LAYERED TROUGH MOVING INTO THE EASTERN UNITED STATES. MEANWHILE...THE FRONTAL BOUNDARY WILL WEAKEN AS IT DRIFTS E OF THE AREA THROUGH THE EARLY PART OF THE WEEK. A SURFACE RIDGE WILL EXTEND FROM THE HIGH PRES OVER THE N CENTRAL ATLC THROUGH THE NORTHERN BAHAMAS MON THROUGH WED AHEAD OF A WEAK FRONTAL BOUNDARY WHICH MAY MOVE OFF THE NE FLORIDA COAST BY THU. GLOBAL MODEL GUIDANCE DIFFERS LATE IN THE WEEK CONCERNING THE DEVELOPMENT OF LOW PRES ALONG THIS BOUNDARY. THE FORECAST FAVORS THE MORE CONSERVATIVE GFS SOLUTION WHICH SHOWS A WEAK LOW DEVELOPING OFF OF JACKSONVILLE BY LATE THU. THE ECMWF IS MUCH MORE AGGRESSIVE AND IS LIKELY EXPERIENCING CONVECTIVE FEEDBACK ISSUES SHOWING A RAPIDLY DEEPENING LOW FRI INTO SAT. NOTE...GRIDDED MARINE OUTPUT IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE (LOWER CASE) GULF OF MEXICO... .NONE. CARIBBEAN SEA... .NONE. ATLANTIC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER CHRISTENSEN