000 AGXX40 KNHC 270546 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 145 AM EDT SAT JUN 27 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 SURFACE RIDGE WILL EXTEND FROM SOUTH FLORIDA INTO TEXAS THROUGH THE PERIOD...KEEPING WINDS AND SEAS FAIRLY MODEST OVER THE NORTHERN GULF. FURTHER SOUTH...A TROPICAL WAVE OVER THE NW CARIBBEAN WILL SHIFT WEST THROUGH THE YUCATAN PENINSULA AND ACROSS THE SOUTHERN BAY OF CAMPECHE THROUGH SUNDAY. A SECOND TROPICAL WAVE WILL FOLLOW THROUGH THE SOUTHERN BAY OF CAMPECHE THROUGH TUESDAY. THE NET IMPACT OF THESE SYSTEMS WILL BE TO INCREASE WINDS SLIGHTLY OVER THE SOUTH CENTRAL GULF WATERS. A CUT OFF UPPER LOW IS MOVING WEST OFF THE YUCATAN PENINSULA INTO THE SW GULF. DIVERGENCE ALOFT ON THE SE SIDE OF THE UPPER LOW WILL ENHANCE THUNDERSTORM ACTIVITY SLIGHTLY OVER THE S CENTRAL AND SW GULF THROUGH EARLY NEXT AS WELL. THE WILD CARD IN ALL THIS THE POTENTIAL FOR TROPICAL CYCLONE DEVELOPMENT OVER THE NW CARIBBEAN IMPACTING THE S CENTRAL GULF. THERE IS A PERSISTENT BUT SO FAR DISORGANIZED CLUSTER OF THUNDERSTORMS OVER THE NW CARIBBEAN. ONE GLOBAL MODEL IS SHOWING FURTHER DEVELOPMENT OVER A TROPICAL CYCLONE THAT WILL MOVE INTO THE SOUTH CENTRAL GULF OVER THE NEXT 48 HOURS. HURRICANE SPECIALISTS ARE GIVING THIS SYSTEM A 30 TO 50 PERCENT CHANCE OF DEVELOPMENT. CURRENT MARINE FORECASTS REFLECT THIS REASONING. CARIBBEAN SEA... A TROPICAL WAVE CURRENTLY MIGRATING WEST THROUGH 84W HAS BEEN INTERACTING WITH SOUTHERLY DIVERGENT FLOW ALOFT BETWEEN A CUT OFF UPPER LOW OVER THE YUCATAN AND AN UPPER ANTICYCLONE OVER JAMAICA TO PRODUCE A LARGE AREA OF PERSISTENT BUT SO FAR DISORGANIZED CONVECTION OVER THE NW CARIBBEAN. SHIP AND BUOY OBSERVATIONS HAVE SHOWED SPORADIC WINDS TO 25 KT AMONG THE CONVECTION...WITH 15 TO 20 KT E TO SE FLOW OUTSIDE OF THE TSTM ACTIVITY OVER THE NW CARIBBEAN. THE TSTMS WILL PERSIST AT LEAST THROUGH TODAY...BUT WILL LIKELY DIMINISH AS THE UPPER LOW AND TROPICAL WAVE SHIFT WEST. FRESH SE FLOW WILL LIKELY CONTINUE THROUGH MID WEEK...EVEN AS THE LOW MOVES INTO THE GULF OF MEXICO. FURTHER EAST...ANOTHER TROPICAL LOW IS EVIDENT NEAR 68W. SCATTEROMETER AND BUOY REPORTS SHOW WINDS OF 20 TO 25 KT OVER THE CENTRAL CARIBBEAN...MAINLY DUE TO THE GRADIENT BETWEEN THE TROPICAL WAVE AND SURFACE RIDGE NORTH OF THE AREA. THE FAR EASTERN AND FAR SW CARIBBEAN ARE SHOWING ONLY 10 TO 15 KT TRADES. THE PERSISTENT STRONG TRADES OVER THE CENTRAL CARIBBEAN HAVE ALLOWED SEAS TO BUILD TO 10 FT OR GREATER BASED ON BUOY REPORTS. EVEN AS THE TROPICAL WAVE MIGRATES THROUGH THE AREA...THE STRONG TRADES WILL PERSIST DUE THE INFLUENCE OF THE SURFACE RIDGE TO THE NORTH. LITTLE CHANGE IS EXPECTED OVER THE CENTRAL CARIBBEAN THROUGH MID WEEK. ATLANTIC S OF 31N W OF 55W... A SURFACE RIDGE EXTENDS E TO W ALONG ROUGHLY 25W AND WILL PERSIST THROUGH MID WEEK. A SERIES OF TROUGHS OR WEAK COLD FRONTS WILL EMERGE OFF THE CAROLINA COAST THROUGH TUE AND MIGRATE EAST. THIS WILL INCREASE THE PRESSURE GRADIENT BETWEEN THE TROUGHS AND THE RIDGE TO THE SOUTH...RESULTING IN HIGHER WINDS AND SEAS OVER THE WATERS MAINLY N OF 27N. GENERALLY LIGHT TO MODERATE FLOW WILL PERSIST UNDER THE INFLUENCE OF THE RIDGE AXIS FROM AROUND 15N TO 27N. S OF 15N CURRENT OBSERVATIONS INDICATE NO MORE THAN 15 KT TRADES...BUT THIS IS LIKELY TO INCREASE TO 20 KT OR SO BY MONDAY AS A TROPICAL WAVE EAST OF THE AREA APPROACHES AND INTERACTS WITH THE RIDGE. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FORECASTER CHRISTENSEN. TROPICAL PREDICTION CENTER.