000 AGXX40 KNHC 290601 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 200 AM EDT SUN APR 29 2012 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... A RIDGE EXTENDS WSW ACROSS ACROSS THE NORTHERN COASTAL WATERS/PLAINS. SLY RETURN FLOW IS AT 15-20 KT ACROSS THE ENTIRE GULF...EXCEPT 5-10 KT OVER THE NE WATERS NEAR THE RIDGE AXIS. STILL EXPECT THE RIDGE TO LIFT N OF THE AREA TONIGHT. THE DEEP LAYERED TROUGH CONTINUES OVER THE SE PORTION AND IS INDUCING A SERIES OF INVERTED LOW TROUGHS THAT WILL MOVE W ACROSS THE SOUTHERN GULF WATERS. THE FIRST TROUGH HAS ALREADY REACHED ABOUT 90W WITH AN ASSOCIATED SLIGHT NE-E WIND SHIFT DETECTED IN THE OBS NETWORK. EXPECT THE MOST SIGNIFICANT LOW LEVEL TROUGH TO MOVE W ACROSS S FL AND THE FL STRAITS TODAY. THE GFS SOLUTIONS ARE FAR MORE AGGRESSIVE THE PAST FEW RUNS THAN ANY OTHER GUIDANCE... THUS BLENDED MUCH HIGHER PERCENTAGES OF ECM AND UKMET INTO THE GRIDS AND GRAPHICAL FORECASTS WHICH WILL HAVE A NE-SE WIND SHIFT WITH A MAX OF 20-25 KT OVER THE SE WATERS THROUGH MON AND THEN DIMINISHING TO 10-15 KT OVER THE S-CENTRAL WATERS TUE-WED WITH TROUGH DIFFUSE ON THU. SW N ATLC FROM 19N TO 31N W OF 55W... A RIDGE EXTENDING E TO W ACROSS THE NORTHERN WATERS WILL WEAKEN AS A WEAK COLD FRONT SWEEPS SE PASSING BERMUDA TONIGHT AND MOVING E OF 55W EARLY MON NIGHT. ELY WINDS ARE CURRENTLY AT 15-20 KT ACROSS ALL WATERS S OF 25N TO THE E OF AN INVERTED TROUGH EXTENDING S TO N ACROSS THE CAY SAL BANK AND THE BAHAMA CHANNEL. THE GRADIENT WILL STRENGTHEN TODAY SUPPORTING E-SE WINDS AT 20-25 KT THROUGHOUT THE NW BAHAMAS AND FL STRAITS AND CONTINUE THROUGH TUE NIGHT...THEN DIMINISHING TO 15 KT WED AND THU. USED A BLEND OF GFS...ECM AND UKMET FOR THE PACKAGE WITH MUCH LESS A PERCENTAGE OF GFS THAN USUAL AS IT APPEARS THE GFS SOLUTIONS ARE CONVECTIVELY CONTAMINATED. CARIBBEAN SEA AND TROPICAL ATLC S OF 19N W OF 55W... A BROAD TROUGH OVER THE NW CARIBBEAN HAS ITS MEAN AXIS TO THE N OF 15N BETWEEN 79W-82W ATTM. THE TROUGH AXIS WILL MOVE W OF THE AREA LATE MON NIGHT. ELY TRADES ENHANCED TO 15-20 KT ACROSS THE TROPICS E OF 80W WILL CHANGE LITTLE THROUGH EARLY MON...THEN DIMINISH TUE THROUGH THU. NOTE... EFFECTIVE APR 3, 2012 AT 1800 UTC THE OFFSHORE WATERS FORECAST ZONES CHANGED FOR THE CARIBBEAN AND SW N ATLANTIC AND THE GULF OF MEXICO. ISSUANCE TIME FOR THE GULF OF MEXICO OFFSHORE WATERS FORECASTS IS REFERENCED TO THE EASTERN TIME ZONE. FOR DETAILS SEE WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF GRIDDED MARINE OUTPUT IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE (LOWER CASE). GULF OF MEXICO... .NONE. CARIBBEAN SEA... .NONE. ATLANTIC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER NELSON