000 AGXX40 KNHC 120757 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 357 AM EDT SAT MAY 12 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 PERSISTENT UPPER LOW CENTERED OVER N CENTRAL TEXAS WILL CONTINUE TO MIGRATE SLOWLY NE TOWARD THE CENTRAL MISSISSIPPI VALLEY. CLUSTERS OF THUNDERSTORMS ARE NOTED N OVER THE NW GULF AHEAD OF THE ADVANCING UPPER DISTURBANCE. A 1009 MB SURFACE LOW ASSOCIATED WITH THE UPPER LOW IS CENTERED OVER S CENTRAL TEXAS AND WILL SHIFT NE TO THE LOWER MISSISSIPPI VALLEY BY EARLY EVENING. AS THE SURFACE LOW TRACKS NE...A WEAK FRONT...POSSIBLY JUST A TROUGH...WILL PUSH OFF THE TEXAS COAST LATER THIS MORNING AND COME INTO PHASE WITH A SURFACE TROUGH OVER THE BAY OF CAMPECHE ALONG 94W S OF 25N. THE FRONT WILL MIGRATE EAST ACROSS THE NORTHERN GULF WATERS THROUGH MON NIGHT. WITH THE EXCEPTION OF THE MODERATE TO FRESH NOCTURNAL NE WINDS OFF THE COAST OF CAMPECHE...A LIGHT FLOW REGIME WILL SET UP THROUGH NEXT THURSDAY. CARIBBEAN SEA AND TROPICAL N ATLC... AN UPPER TROUGH MIGRATING THROUGH THE EASTERN CARIBBEAN THAT HAS BEEN RESPONSIBLE FOR HEAVY SHOWERS AND THUNDERSTORMS THE PAST COUPLE OF DAYS OVER THE LEEWARD AND WINDWARD ISLANDS CONTINUES TO PUSH EASTWARD...WITH THE AXIS OF THE UPPER TROUGH GENERALLY OVER THE ISLAND CHAIN. INSTABILITY ON THE EAST SIDE OF THE TROUGH CONTINUES TO PRODUCES AREAS OF SHOWERS AND THUNDERSTORMS...BUT THIS ACTIVITY IS EAST OF THE ISLANDS...TO INCLUDE BARBADOS. IN ADDITION THE TROUGH IS STARTING TO DEAMPLIFY AND THE FORCING ON THE EAST SIDE OF THE TROUGH IS DIMINISHING...ALLOWING THE CONVECTION TO WEAKEN. THE MAIN WEATHER IMPACT THROUGH THE MIDDLE OF NEXT WEEK WILL BE FRESH TO STRONG EASTERLY WINDS FROM THE TROPICAL N ATLC WATERS E OF THE WINDWARDS...ACROSS THE CARIBBEAN TO NEAR 80W. PERSISTENT HIGH PRES WELL N OF THE REGION MAINTAIN THE ENHANCED EAST FLOW. THERE IS ALSO SOME HINT OF A LOW LATITUDE/LOW AMPLITUDE TROPICAL WAVE MOVING ACROSS NORTHERN SOUTH AMERICA...ALTHOUGH EVIDENCE OF THIS IS VERY SUBTLE ESPECIALLY GIVEN THE COMPLEX TERRAIN AND DIURNAL INFLUENCES IN THAT AREA. IF THIS FEATURE DOES EXIST...IT WILL EXPLAIN THE PERSISTENCE AND STRENGTH OF THE EAST WINDS OVER THE CENTRAL CARIBBEAN THROUGH EARLY NEXT WEEK AS DEPICTED BY BOTH THE GFS AND ECMWF. SEAS WILL BUILD AS HIGH AS 11 FT IN E SWEL OFF THE COLOMBIAN COAST. FURTHER WEST...LOCAL WINDS OVER THE GULF OF HONDURAS WILL OCCASIONALLY REACH 20 KT...MAINLY OVERNIGHT. OTHERWISE LIGHT TO MODERATE EAST WINDS WILL PERSIST OVER THE NW CARIBBEAN THROUGH THE MIDDLE OF NEXT WEEK. SW N ATLANTIC... A WEAKENING COLD FRONT FROM 31N64W TO 26N78W WILL GLIDE E OF THE AREA THROUGH TONIGHT. SCATTERED CONVECTION NOTED ALONG THE FRONTAL BOUNDARY WILL DIMINISH AND SHIFT EAST AS WELL THROUGH MIDDAY. HIGH PRES BUILDING EAST FROM THE CAROLINAS WILL MAINTAIN MODERATE TO FRESH NE TO E WINDS MAINLY N OF 25N THROUGH LATE SUN. GLOBAL MODELS ARE IN SLIGHTLY BETTER AGREEMENT SHOWING THE DEVELOPMENT OF LOW PRES BY LATE MON OVER GEORGIA. THE LOW WILL SHIFT NE THROUGH THE CAROLINAS THROUGH MID WEEK WITH A WEAK TRAILING FRONT OR TROUGH EMERGING OFF THE NE FLORIDA COAST BY LATE WED. MODERATE TO FRESH SE TO S BREEZES WILL PERSIST AHEAD OF THE LOW IN THE WATERS BETWEEN THE NORTHERN BAHAMAS AND BERMUDA MON AND TUE. NOTE... EFFECTIVE APR 3 2012 AT 1800 UTC THE OFFSHORE WATERS FORECAST ZONES CHANGED FOR THE CARIBBEAN AND SW N ATLANTIC AND THE GULF OF MEXICO. ISSUANCE TIME FOR THE GULF OF MEXICO OFFSHORE WATERS FORECASTS IS REFERENCED TO THE EASTERN TIME ZONE. FOR DETAILS SEE WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF GRIDDED MARINE OUTPUT IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE GULF OF MEXICO... .NONE. CARIBBEAN SEA... .NONE. ATLANTIC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER CHRISTENSEN