000 AGXX40 KNHC 250649 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 245 AM EDT MON MAY 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... LIGHT S TO SW WINDS PERSIST ACROSS THE GULF OF MEXICO THIS MORNING...FLOWING INTO THE 1003 MB LOW STILL PARKED OVER ARKANSAS. A SHARP UPPER TROUGH REMAINS IN PLACE FROM MISSISSIPPI TO CENTRAL FLORIDA. A WEAK UPPER DISTURBANCE IN THE ZONAL FLOW SOUTH OF THE TROUGH IS AIDING MODEST CONVECTION OVER THE EASTERN GULF. THE PATTERN THROUGH THE WEEK WILL BE A WEAK RIDGE EXTENDING ACROSS THE GULF FROM FLORIDA THROUGH THE BAY OF CAMPECHE. THE LOW TRACKS NORTH LEAVING A WEAK TROUGH OVER TEXAS. MODERATE SOUTHERLY FLOW WILL INCREASE TO BARELY 20 KT OVER PARTS OF THE FAR WESTERN GULF BETWEEN THE RIDGE AND THE TROUGH STARTING LATE TODAY THROUGH WED. A SHORT WAVE TROUGH WILL MOVE INTO THE CENTRAL MISSISSIPPI VALLEY WED INTO THU...AND WILL SPONSOR A WEAK COLD FRONT THAT WILL STALL AND DISSIPATE OVER THE FAR NW GULF THU INTO FRI. THERE MAY BE A SLIGHT INCREASE IN SW WINDS OVER THE N CENTRAL AND NE GULF AHEAD OF THIS FRONT...BUT OTHERWISE LITTLE CHANGE IS EXPECTED. CARIBBEAN AND TROPICAL ATLC W OF 55W... PRESSURE GRADIENT BETWEEN HIGH PRES NE OF BERMUDA NEAR 35N60W AND LOWER PRESSURE OVER SOUTH AMERICA IS CONTINUING TO PRODUCE A SWATH OF 20 KT TRADE WINDS OVER THE SE CARIBBEAN AND 15-20 KT ACROSS MUCH OF THE REMAINDER OF THE EASTERN AND CENTRAL CARIBBEAN. ELSEWHERE IN THE WESTERN CARIBBEAN AND OVER ATLC WATERS BETWEEN 55W AND THE ISLANDS...TROUGHS TO THE NORTH OF THESE RESPECTIVE AREAS ARE MAINTAINING ONLY 10-15 KT FLOW. A TROPICAL WAVE IS NOTED ALONG 57W...AND WILL SHIFT WEST INTO THE EASTERN CARIBBEAN TUE. WINDS WILL START TO INCREASE EAST OF THE WINDWARDS BY WED AS THE TROUGHING TO THE NORTH BREAKS DOWN AND THE ATLC RIDGE BUILDS SW...IN THE WAKE OF THE TROPICAL WAVE. SIMILARLY...WINDS WILL PICK UP SLIGHTLY OVER THE NW CARIBBEAN BY MIDWEEK AS THE RIDGE BUILDS OVER THE GULF OF MEXICO. SUBTROPICAL ATLANTIC W OF 55W... RECENT BUOY OBSERVATIONS AND A 0220Z ASCAT PASS SHOW A BROAD SWATH OF 15 TO 20 KT PARALLELING THE LENGTH OF THE BAHAMAS. THESE WINDS ARE SANDWICHED BETWEEN A 1024 MB SURFACE HIGH PRES NE OF BERMUDA...AND WEAK TROUGHING TO THE WEST. BUOYS SHOW SEA HEIGHTS 7 FT OR LESS IN THIS SWATH...WITH 3 TO 5 FT ELSEWHERE. A SHARP UPPER TROUGH REMAINS IN PLACE FROM THE MISSISSIPPI DELTA SE THROUGH S FLORIDA...WITH AN UPPER JET SOUTH OF THE TROUGH EXTENDING OVER CUBA. A SMALL CLUSTER OF CONVECTION IS FLARING OVER THE CENTRAL BAHAMAS NEAR LONG ISLAND...UNDER AN AREA OF UPPER DIVERGENCE AND THE LEFT FRONT EXIT AREA OF THE JET. THE MAIN FORECAST ISSUE FOR THE NEXT SEVERAL DAYS REMAINS THE DEVELOPMENT OF A SURFACE TROUGH IN THE BAHAMAS. THE GFS SEEMS TO STILL BE SUFFERING CONVECTIVE FEEDBACK ISSUES...AND DEEPENS A SURFACE LOW NE OF ELEUTHERA LATE TODAY...THEN TRACKS IT DUE NORTH THROUGH TUE WITH WINDS REACHING 30 KT. THIS REMAINS MORE AGGRESSIVE THAN OTHER MODELS...AND THE FORECAST REFLECTS A MORE SUBDUED TROUGH DEVELOPMENT INSTEAD. GIVEN CURRENT 15 TO 20 KT FLOW...EXPECT AREA OF 20 KT WIND TO EXPAND NE OF THE BAHAMAS THROUGH WED. THE OVERLY STRONG WINDS OF THE GFS ARE REFLECTED IN THE WW3 OUTPUT...SO WENT A LITTLE LOWER IN THE FORECAST. THE TROUGH WILL SHIFT N OF THE AREA THROUGH WED...LEAVING A RIDGE OF HIGH PRES IN PLACE FROM THE CENTRAL ATLC THROUGH THE SOUTHERN BAHAMAS THU AND FRI. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FORECASTER CHRISTENSEN. TROPICAL PREDICTION CENTER.