000 AGXX40 KNHC 181824 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE MIAMI FL 224 PM EDT SAT JUL 18 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... CLUSTERS OF THUNDERSTORMS PERSIST OVER THE NORTHERN GULF OF MEXICO THIS AFTERNOON...ALONG A PRE-FRONTAL TROUGH AHEAD OF A WEAK COLD FRONT MOVING THROUGH THE DEEP SOUTH STATES. FURTHER SOUTH...A 1020 MB SURFACE HIGH PRES AREA IS CENTERED OVER THE SOUTHEAST GULF OFF SW FLORIDA. WINDS OUTSIDE OF THUNDERSTORMS REMAIN FAIRLY LIGHT ACROSS THE GULF...WITH THE EXCEPTION OF THE EASTERN BAY OF CAMPECHE WHERE A MORNING QUIKSCAT PASS SHOWED UP TO 20 KT WINDS...LIKELY ASSOCIATED WITH A TROPICAL WAVE THAT IS TRANSITING WESTWARD TO THE SOUTH OF THE AREA. THE COLD FRONT WILL PUSH INTO THE FAR NE GULF LATE TODAY...THEN STALL ON SUNDAY AND BECOME DIFFUSE BY MONDAY. IN THE MEANWHILE...A DEEPENING UPPER TROUGH OVER THE EASTERN U.S. WILL ENHANCE THUNDERSTORMS OVER MOSTLY THE NORTHERN GULF NEAR THE FRONT. THE RIDGE WILL REMAIN IN PLACE...MAINTAINING GENERALLY LIGHT TO MODERATE WINDS INTO EARLY NEXT WEEK. THE WINDS OVER THE SOUTHERN BAY OF CAMPECHE WILL DIMINISH THROUGH SUNDAY AS THE TROPICAL WAVE MOVES EAST. BY MIDWEEK...THE SUBTROPICAL RIDGE BUILDS OVER THE WESTERN ATLC AND INTO THE GULF. THIS WILL ALLOW SLIGHTLY STRONGER RETURN FLOW OVER THE WESTERN GULF OF MEXICO. CARIBBEAN... AN EARLY MORNING QUIKSCAT SHOWED DEFINITE 25 KT WINDS WITH SEVERAL RAIN FLAGGED REPORTS OF 30 KT STILL GOING OFF THE COAST OF COLOMBIA IN THE SW CARIBBEAN. THESE STRONG TRADES ARE THE RESULT OF FAIRLY HIGH PRES TO THE NORTH OF THE AREA. AS THE HIGH PRES WEAKENS OVER THE NEXT DAY OR SO...WINDS WILL DIMINISH SOMEWHAT OVER THE SW CARIBBEAN...ALTHOUGH 25 KT ALONG THE IMMEDIATE COAST IS NOT OUT OF THE QUESTION THROUGH THE MIDDLE OF NEXT WEEK. SEAS ARE ESTIMATED TO BE 13 FT IN E SWELL AND SUBSIDING. ELSEWHERE IN THE CARIBBEAN...THE MAIN WEATHER INFLUENCE WILL BE A TROPICAL WAVE CURRENTLY PASSING TO THE WEST OF THE LESSER ANTILLES. THIS FEATURE WILL BRING A BROAD AREA OF SHOWERS AND TSTMS TO THE NORTHEAST CARIBBEAN AND LEEWARD ISLANDS...ALONG WITH INCREASED WINDS AND SEAS SUN INTO MON. THE CONVECTION IS IN PART ENHANCED BY A PERSISTENT UPPER TROUGH TO THE NE OF THE LEEWARD ISLANDS. THE TROPICAL WAVE IS MOVING FAIRLY QUICKLY AT 15 KT...AND WILL REACH THE CENTRAL CARIBBEAN BETWEEN COLOMBIA AND HAITI BY EARLY MON. THE TROPICAL WAVE WILL SLOW A LITTLE AS IT PUSHES INTO THE CENTRAL AND SW CARIBBEAN...REACHING 80W BY TUE...AND THE NICARAGUAN COAST BY MIDWEEK. EXPECT A SURGE OF TRADE WINDS BEHIND THE WAVE TO 25 KT. SEAS WILL BRIEFLY INCREASE WITH THE TROPICAL WAVE PASSAGE...BUT OVERALL WILL ACTUALLY CONTINUE TO SUBSIDE GIVEN THE DECAYING SWELL AND THE FACT THAT THE DURATION OF THE ENHANCED WINDS BEHIND THE TROPICAL WAVE WILL BE MINIMAL. A SECOND TROPICAL WAVE CURRENTLY OVER THE CENTRAL ATLC WILL PUSH INTO THE EASTERN CARIBBEAN BY EARLY MONDAY...REACHING ROUGHLY 68W BY EARLY TUE...AND JAMAICA BY WED. ATLANTIC S OF 31N W OF 55W... A PROMINENT SURFACE RIDGE EXTENDS FROM THE AZORES THROUGH THE CENTRAL BAHAMAS AND S FLORIDA. A TRIO OF TROPICAL WAVES ARE NOTED OVER THE TROPICAL ATLC WATERS FURTHER SE. THE FIRST MENTIONED ALREADY IS MOVING INTO THE ERN CARIB. THE SECOND ALONG 43W...AND A THIRD SMALLER WAVE WAS APPROACHING 32W. THE NRN PORTION OF THIS FIRST WAVE WILL TAKE A W-NW MOTION AND CROSS THE NE CARIB TODAY AND SUN...REACH 70W SUN NIGHT...AND MOVE INTO THE SE BAHAMAS MON. A BROAD WIND SURGE ACROSS THE TOP OF THIS WAVE WILL BRING A SIGNIFICANT INCREASE IN SEAS TO THE BAHAMAS AND ATLC WATERS TO THEIR E BY MON...BUILDING 7 TO 8 FT OR HIGHER. SQUALLS AND TSTMS WILL ALSO ACCOMPANY THIS WAVE INTO THE BAHAMAS. OTHERWISE...THE ATLC RIDGE WILL SHIFT SLIGHTLY W AND NW DURING THE NEXT SEVERAL DAYS AND TIGHTEN THE PRES GRADIENT IN CONJUNCTION WITH THE TROPICAL WAVE TO BRING INCREASING E TO SE WINDS OF 20 TO 25 KT OVER THE WATERS TO THE NORTH PUERTO RICO ACROSS THE SOUTHERN BAHAMAS AND TURKS AND CAICOS THROUGH MIDWEEK. WINDS AND SEAS START TO DIMINISH LATER IN THE WEEK AS THE TROPICAL WAVE ACTIVITY RELAXES TO THE SOUTH AND THE SUBTROPICAL RIDGE SHIFTS SOUTHWARD. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. $$ $$ FORECASTER CHRISTENSEN