000 AGXX40 KNHC 251733 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 133 PM EDT SAT JUL 25 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... THE SOUTHERN EXTENT OF AN UPPER TROUGH MOVING THROUGH THE MISSISSIPPI VALLEY INTO THE EASTERN U.S. HAS BEEN DIGGING INTO THE GULF OF MEXICO THIS MORNING. COLDER AIR ALOFT NEAR THE TROUGH AXIS WAS ENHANCING CLUSTERS OF CONVECTION OVER THE NORTHERN GULF FROM NEAR THE MISSISSIPPI RIVER DELTA TO APPALACHICOLA FL. IN ADDITION...DIVERGENT FLOW ALOFT ON THE SE SIDE OF THE UPPER TROUGH WAS GENERATING A BROKEN LINE OF CONVECTION FROM NORTH OF THE YUCATAN PENINSULA THROUGH SOUTH FLORIDA AND INTO THE FAR WESTERN ATLC. A SURFACE RIDGE EXTENDS FROM THE WESTERN ATLC THROUGH A 1017 MB SURFACE HIGH PRES AREA OVER THE EASTERN U.S. THEN ON TOWARD THE TEXAS COAST. BUOY AND SCATTEROMETER DATA SHOW GENERALLY LIGHT WINDS OVER MOST OF THE GULF DUE TO THE SURFACE RIDGE POSITION. THE EXCEPTION IS IN THE BAY OF CAMPECHE...WHERE A TIGHT PRESSURE GRADIENT IS PRESENT BETWEEN THE SURFACE RIDGE AND A TROPICAL WAVE MIGRATING WESTWARD THROUGH GUATEMALA AND SOUTHERN MEXICO. SCATTERED TSTMS MAY CONTINUE OVER THE EASTERN GULF THROUGH SUNDAY AS THE COOLER AIR ALOFT MOVES FURTHER SE OVER THE WARMER LOOP CURRENT. THE TSTM ACTIVITY WILL SUBSIDE INTO MONDAY AS THE AIR ALOFT MODIFIES AND THE UPPER TROUGH DAMPENS OUT. WINDS OVER THE SW GULF WILL BE GENERALLY 10 TO 15 KT INTO MONDAY...OCCASIONALLY INCREASING TO 15 TO 20 KT ALONG THE YUCATAN COAST IN THE EVENING...AND WHEN A SECOND TROPICAL WAVE MOVES S OF THE AREA THROUGH SUNDAY. TOWARD MID WEEK...SE RETURN FLOW WILL INCREASE AS LOW PRES DEVELOPES OVER WEST TEXAS. ELSEWHERE LIGHT TO MODERATE FLOW WILL PERSIST OUTSIDE OF TSTMS. CARIBBEAN... AN OVERNIGHT ASCAT PASS REVEALED 25 TO 30 KT WINDS OFF THE COLOMBIAN COAST...JIVING WITH REPORTS FROM BUOY 42058 IN THE CENTRAL CARIBBEAN SHOWING 25 KT SUSTAINED WINDS. 20 KT WINDS ARE NOTED IN THE GULF OF HONDURAS AS A TROPICAL WAVE IS MOVING WEST THROUGH 80W. THE STRONG FLOW IN THE S CENTRAL CARIBBEAN IS DUE THE INTERACTION BETWEEN THE WAVE AND A SURFACE RIDGE N OF THE AREA. THE WAVE WILL SHIFT W OF THE AREA THROUGH SUNDAY...ALLOWING WINDS TO DIMINISH SLIGHTLY OVER THE S CENTRAL CARIBBEAN. HOWEVER THE SURFACE RIDGE WILL REMAIN IN PLACE TO THE NORTH...KEEPING AT LEAST 25 KT TRADES IN PLACE OFF COLOMBIA THROUGH MIDWEEK. WINDS OVER THE EASTERN CARIBBEAN ARE ONLY 10 TO 15 KT CURRENTLY. HIGH PRES BUILDS NEAR BERMUDA FROM TONIGHT THROUGH TUESDAY...ALLOWING TRADES TO INCREASE FROM THE EASTERN TO CENTRAL CARIBBEAN INTO MID WEEK. COMBINED SEAS ARE PERHAPS AS HIGH AS 14 FT OFF COLOMBIA DUE IN PART TO EAST SWELL. AS WINDS INCREASE OVER THE EASTERN CARIBBEAN...SEAS WILL BUILD TO AS HIGH AS 13 FT IN E SWELL BY LATE TUE. ATLANTIC S OF 31N W OF 55W... CLUSTERS OF TSTMS ARE NOTED MAINLY N OF THE BAHAMAS THIS MORNING...ON THE SE SIDE OF AN UPPER TROUGH OVER THE GULF OF MEXICO. A SURFACE RIDGE EXTENDS FROM THE N CENTRAL ATLC TO JUST SOUTH OF BERMUDA...THROUGH THE NORTHERN BAHAMAS. A WEAK SURFACE TROUGH IS NOTED USING BUOY AND QUIKSCAT DATA EXTENDING FROM JUST NE OF THE TURKS/CAICOS TO 27N67W. WINDS ARE GENERALLY 10 TO 15 KT FROM E OF THE LEEWARDS TO THE SOUTHERN BAHAMAS AND AROUND THE SURFACE RIDGE...ALTHOUGH 20 KT E FLOW IS NOTED N OF HAITI. FURTHER TO THE SE...15 TO 20 KT TRADES ARE NOTED E OF THE WINDWARD ISLANDS. THE TREND THROUGH MIDWEEK IS GOING TO BE INCREASING TRADE WINDS AND BUILDING SEAS S OF 22N AS HIGH PRES BUILDS NEAR BERMUDA WITH THE RIDGE EXTENDING ALONG 28N/29N. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. $$ FORECASTER CHRISTENSEN