000 AGXX40 KNHC 201904 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE MIAMI FL 304 PM EDT MON JUL 20 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... A FRONTAL BOUNDARY REMAINS STATIONARY OVER THE NE GULF OF MEXICO THIS AFTERNOON. A RIDGE OF HIGH PRES EXTENDS FROM THE WESTERN ATLC THROUGH S FLORIDA AND INTO THE GULF TOWARD A 1018 MB HIGH PRES AREA CENTERED NEAR 26N91W. AN UPPER TROUGH OVER THE EASTERN U.S. HAS BECOME MORE AMPLIFIED OVER THE EASTERN GULF. THE DEEP LAYER MOISTURE HAS BEEN SHUNTED EASTWARD OVER THE FLORIDA PENINSULA AND WESTERN ATLC AS THE TROUGH HAS DUG SOUTH. A FEW TSTMS REMAIN OVER THE SE GULF AHEAD OF THE BASE OF THE TROUGH...BUT OTHERWISE THE GULF REMAINS FREE OF CONVECTION. THIS WILL CHANGE TONIGHT OVER THE NW GULF...WHERE SHORT WAVE ENERGY WILL PUSH SOUTHWARD ON THE WEST SIDE OF THE UPPER TROUGH...IGNITING ADDITIONAL TSTMS OFF THE TEXAS COAST. LIGHT TO MODERATE WINDS PERSIST OVERALL...ALTHOUGH QUIKSCAT AGAIN SHOWED FRESH TO STRONG SE WINDS OVER THE EASTERN BAY CAMPECHE. THIS HAS BEEN AN ISSUE EVERY MORNING FOR THE PAST THREE DAYS. IT ORIGINALLY WAS DUE TO A PASSING TROPICAL WAVE THAT IS NOW WELL TO THE WEST. THE RECENT SE WINDS ARE LIKELY DUE TO THE PRESENCE OF AN UPPER TROUGH EXTENDING FROM THE NORTHERN YUCATAN TO THE GULF OF TEHUANTEPEC. THIS MAY BE INDUCING A WEAK INVERTED TROUGH OVER GUATEMALA AND MEXICO...WHICH IS INTERACTING WITH THE SURFACE OVER THE GULF OF MEXICO TO ENHANCE MORNING DRAINAGE FLOW OVER THE EASTERN BAY OF CAMPECHE. THIS UPPER FEATURE BREAKS DOWN THROUGH LATE TUE...WEAKENING THE GRADIENT. LOOKING AHEAD...THE FRONT BREAKS DOWN THROUGH TUE...ALLOWING THE RIDGE TO REBUILD OVER THE GULF. THIS WILL ENHANCE RETURN FLOW SLIGHTLY OVER THE W AND SW GULF WATERS THROUGH WED. CARIBBEAN... A TROPICAL WAVE ALONG 78W WILL PUSH THROUGH THE WESTERN CARIBBEAN AND GULF OF HONDURAS THROUGH LATE TUE...AS ANOTHER TROPICAL WAVE ENTERS THE EASTERN CARIBBEAN THIS EVENING. THE SECOND TROPICAL WAVE WILL TRACK WEST ACROSS THE BASIN THROUGH THU...FOLLOWED BY A THIRD WEAKER TROPICAL WAVE ENTERING THE EASTERN CARIBBEAN BY LATE WED. THE NET EFFECT OF THESE WAVES WILL BE FAIRLY SQUALLY WEATHER FOR MAINLY THE NE CARIBBEAN THROUGH THE LESSER ANTILLES AS THE SECOND TROPICAL WAVE MOVES ACROSS THE REGION TONIGHT. THE INTERACTION OF THE TROPICAL WAVES WITH HIGH PRES N OF THE AREA WILL KEEP FRESH TO STRONG WINDS IN PLAY ACROSS THE MAINLY THE EASTERN AND CENTRAL CARIBBEAN THROUGH THE REMAINDER OF THE WEEK. TRADES WILL INCREASE TO 30 KT AGAIN OFF THE COLOMBIAN COAST BY THU. THE PERSISTENT STRONG EAST WINDS WILL ALLOW SEAS TO BUILDS ESPECIALLY OVER THE SOUTH CENTRAL CARIBBEAN TO IN EXCESS OF 12 FT BY LATE IN THE WEEK. ATLANTIC S OF 31N W OF 55W... THE TROPICAL ATLC WATERS E OF THE LESSER ANTILLES AND N OF GUYANA WILL SEE A SERIES OF TROPICAL WAVES MIGRATE ACROSS OVER THE NEXT SEVERAL DAYS. A TROPICAL WAVE CURRENTLY NEAR BARBADOS WILL BRING HEAVY RAINS AND GUSTY WINDS TO THE WATERS AROUND THE WINDWARD ISLANDS TONIGHT. TRADE WINDS PARTICULARLY N OF 15N WILL REMAIN FRESH TO STRONG AS THE WAVES MARCH WEST...ALLOWING SEAS TO BUILD TO 12 FT IN E SWELL OVER MAINLY THE AREA GOING INTO THE LEEWARDS. FURTHER NORTH...THESE WINDS AND SEAS WILL INCREASE IN THE AREA FROM THE LEEWARDS THROUGH THE TURKS AND CAICOS...AND FURTHER ON TO THE SOUTHERN BAHAMAS. AN UPPER TROUGH OVER THE AREA WILL HELP AMPLIFY THE NORTHERN EXTENTS OF THE A PAIR OF TROPICAL WAVES MIGRATING THROUGH THE CARIBBEAN...AND WILL ALLOW THEM TO SPLIT OFF AS INVERTED TROUGHS AND RIDE NW AROUND THE EDGE OF THE SUBTROPICAL RIDGE...PUSHING THROUGH THE BAHAMA CHAIN AND INTO THE WATERS N OF THE BAHAMAS AND INTO SE FLORIDA THROUGH THU. THE UPPER TROUGH WILL ALSO HELP ADD TO THE CONVECTION IN THE AREA N OF HISPANIOLA THROUGH WED. WINDS AND SEAS DIMINISH A LITTLE LATE IN THE WEEK AFTER THE TROPICAL WAVES MIGRATE S OF THE AREA. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. $$ $$ FORECASTER CHRISTENSEN