000 AGXX40 KNHC 130738 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 338 AM 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 APPEARS TO BE STALLING AS AN UPPER TROUGH LIFTS OUT THROUGH THE LOWER MISSISSIPPI VALLEY TOWARD THE CAROLINAS. THE FRONT WILL WEAKEN AND MAKE VERY SLOW PROGRESS EASTWARD THE UPPER SUPPORT CONTINUES TO LIFT 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 GULF. THIS WILL DIMINISH AS THE UPPER TROUGHING LIFTS OUT. REGIONAL OBSERVATIONS SHOW THE FRONT TO BE VERY WEAK AND ILL DEFINED. IT WILL DRIFT SLOWLY EAST ACROSS THE NORTHERN GULF...BEFORE STALLING AND DISSIPATING BY LATE TUE OVER THE NE GULF. A SURFACE RIDGE WILL BUILD ACROSS THE NORTHERN GULF ALONG 28N IN THE WAKE OF THE WEAK BOUNDARY. FURTHER SOUTH...A PERSIST BROAD SURFACE TROUGH OVER THE BAY OF CAMPECHE WILL MOVE LITTLE OVER THE NEXT COUPLE OF DAYS BEFORE BECOMING DIFFUSE BY TUE. THE WEAK PRES PATTERN WILL MAINTAIN LIGHT TO MODERATE WINDS AND SEAS THROUGH MID WEEK. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... AN UPPER LEVEL TROUGH EXTENDS FROM 25N65W SOUTHWARD ACROSS THE VIRGIN ISLANDS TO NEAR LAKE MARACAIBO. ALTHOUGH CONVECTION FROM YESTERDAY HAS LARGELY DISSIPATED FROM HISPANIOLA TO THE LEEWARD ISLANDS...THE TROUGH IS DRIFTING SLOWLY EAST AND WILL KEEP WEATHER UNSETTLED IN THIS AREA THROUGH TONIGHT...BEFORE THE TROUGH DAMPENS OUT AND SHIFTS FURTHER EAST INTO THE ATLANTIC. OTHERWISE...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 80W...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 EAST WINDS WILL PERSIST OVER THE NW CARIBBEAN THROUGH THE MIDDLE OF NEXT WEEK. SW N ATLANTIC S OF 31N W OF 55W... A WEAK FRONTAL BOUNDARY EXTENDS FROM 31N59W TO 27N65W...WITH A SHEAR LINE EXTENDING TO 24N73W. HIGH PRES BETWEEN THE CAROLINAS AND BERMUDA IS PROMOTING FRESH NE FLOW N OF 25N THROUGH THE NORTHERN BAHAMAS AND INTO EASTERN FLORIDA. THESE WINDS DIMINISH THROUGH TONIGHT AS THE HIGH PRES MOVES INTO THE N CENTRAL ATLANTIC AHEAD OF A DEEP LAYER TROUGH MOVING INTO THE EASTERN UNITED STATES. THIS WILL ALLOW THE SHEAR LINE TO BECOME DIFFUSE THROUGH TODAY. THE FRONTAL BOUNDARY WILL WEAKEN AS IT DRIFTS EAST OF THE AREA. MEANWHILE FURTHER SOUTH...AN UPPER TROUGH EXTENDING FROM 25N65W SOUTHWARD ACROSS THE VIRGIN ISLANDS WILL KEEP WEATHER UNSETTLED S OF 22N E OF 70W TODAY. 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 MOVING OFF THE NE FLORIDA COAST BY THU. GLOBAL MODELS DIFFER TOWARD LATER IN THE WEAK CONCERNING THE DEVELOPMENT OF LOW PRES ALONG THIS BOUNDARY. FORECAST FAVORS THE MORE CONSERVATIVE GFS SHOWING A WEAK LOW DEVELOPMENT BETWEEN OFF 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