000 AGXX40 KNHC 301948 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 350 PM EDT SAT MAY 30 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... ASIDE FROM HIGH WINDS AND SEAS ASSOCIATED WITH CONVECTIVE ACTIVITY...THE FORECAST PERIOD WILL BE RELATIVELY PLACID IN THE GULF OF MEXICO WITH WINDS LESS THAN 15 KT AND SEAS GENERALLY 2 TO 3 FEET. THE COLD FRONT CURRENTLY OVER THE CENTRAL GULF WILL DISSIPATE TO A TROUGH BY THE END OF THE WEEKEND. THE LINGERING TROUGH WILL LIFT NORTH THROUGH THE EASTERN GULF AND BE A FOCUS FOR CONVECTION THROUGH WED. OTHERWISE...A WEAK FRONT WILL APPROACH THE NE GULF COAST MON. ANOTHER FRONT IS EXPECTED TO MOVE INTO NW GULF WATERS ON THU...BUT CONFIDENCE IS LOW AS THE GFS IS WEAKER AND MORE NORTHERLY WITH THIS FRONT THAN THE ECMWF. CARIBBEAN... STRONG TRADES WILL CONTINUE THROUGH THE PERIOD. THE SUBTROPICAL HIGH PRES SYSTEM WILL WEAKEN SLIGHTLY AS IT SHIFTS EASTWARD THROUGH TUE...BUT IT WILL BE REINFORCED AS IT MERGES WITH HIGH PRES BEHIND THE DISSIPATING COLD FRONT PASSING THROUGH BERMUDA MON/TUE. A TROPICAL WAVE CURRENTLY ALONG 23W S OF 11N WILL MOVE INTO THE SE CARIBBEAN SUN...PASS 70W ON TUE...AND MOVE INTO THE SW CARIBBEAN ON THU. THE WAVE WILL BE MOVING UNDER A REGION OF UPPER LEVEL CONFLUENCE ON THE SE SIDE OF THE UPPER LOW N OF PUERTO RICO AND THE UPPER LEVEL RIDGE AXIS ASSOCIATED WITH AN ANTICYCLONE CENTERED NEAR 04N32W. THIS CONFLUENCE MAY INHIBIT CONVECTION NEAR THE TROPICAL WAVE AS IT PASSES INTO THE EASTERN CARIBBEAN. TROPICAL ATLC... ASIDE FROM THE TROPICAL WAVE MENTIONED IN THE CARIBBEAN SECTION ABOVE...THERE IS A TROPICAL WAVE NEAR 22N THAT IS EXPECTED TO MOVE RAPIDLY W UNDER THE SUBTROPICAL HIGH THROUGH THE TROPICAL ATLC REACHING 40W TUE AND APPROACHING THE NE COAST OF SOUTH AMERICA LATE THU. ONCE THE WAVE PASSES E OF THE UPPER LEVEL ANTICYCLONE CURRENTLY NEAR 04N32W...IT WILL BE UNDER A REGION OF UPPER LEVEL DIFFLUENCE WHICH SHOULD BE FAVORABLE FOR THE ENHANCEMENT OF CONVECTION. THERE IS SOME DISAGREEMENT LATE IN THE PERIOD BETWEEN THE MODELS CONCERNING THE STRENGTHENING OF MID LEVEL VORTICITY ASSOCIATED WITH THE ITCZ. UNTIL THERE IS MORE EVIDENCE FOR THIS DEVELOPMENT...WILL PLAY DOWN THE POSSIBILITY IN THE FORECAST. SW N ATLC... WEAK COLD FRONT CURRENTLY ALONG THE NE FL COAST WILL WEAKEN OVER THE NEXT DAY OR SO. THE MID LEVEL TROUGH ASSOCIATED WITH THIS COLD FRONT WILL TURN NEGATIVE TILT OVER NEW ENGLAND AND THE CANADIAN MARITIMES AS A DEEP LAYER LOW TO THE WEST DROPS INTO THE GREAT LAKES AND INTO THE BROAD TROUGH OVER THE EASTERN UNITED STATES. THE ASSOCIATED REINFORCING COLD FRONT WILL MOVE OFF THE MID ATLC COAST...NORTH OF FORECAST WATERS...AND HELP CARRY WHAT IS LEFT OF THE FRONT CURRENTLY OVER THE SW N ATLC EASTWARD. THE SUBTROPICAL RIDGE WILL REBUILD OVER THE SW N ATLC MON AND TUE AS THE HIGH PRES SYSTEM BEHIND THE REINFORCING COLD FRONT MERGES WITH THE SUBTROPICAL HIGH...BRINGING DOMINANTLY SE FLOW TO THE REGION FOR THE REST OF THE PERIOD. EXPECT WINDS TO INCREASE THU OVER NW WATERS AS A COLD FRONT MOVES INTO THE SE UNITED STATES. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FORECASTER SCHAUER CLARK. TROPICAL PREDICTION CENTER.