000 AGXX40 KNHC 200749 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 400 AM EDT WED MAY 20 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO AND SW N ATLC... AFTER A BRIEF REPRIEVE TUE FROM GALE FORCE WINDS SEEN LAST NIGHT AT BUOY SGOF1...GALES HAVE RETURNED TO THE NE GULF OF MEXICO ASSOCIATED WITH THE TIGHT PRESSURE GRADIENT BETWEEN 1007 LOW PRES OVER SW FL AND 1031 MB HIGH PRES MOVING OFF THE DELMARVA COAST. FROM 2300 UTC ONWARD...THIS BUOY JUST S OF APALACHICOLA HAS BEEN REPORTING GALES TO 39 KT G 41KT. MEANWHILE...BUOY 42036 HAS BEEN HOVERING JUST BELOW GALE FORCE SINCE AROUND 0000 UTC. THE 0226 ASCAT PASS CONFIRMED GALE CONDITIONS NEAR 29N84W WHILE AN EARLIER SFMR DATA FROM A RECONNAISSANCE MISSION REPORTED GALES NEAR 28N86W. IN THE SW N ATLC...GALES HAVE BEEN REPORTED AS FAR SOUTH AS AT BUOY 41009 OFF CAPE CANAVERAL. WINDS ARE EXPECTED TO DROP BELOW GALE FORCE IN BOTH LOCALES OVER THE NEXT 24 HOURS AS THE DEEP LAYER LOW MOVES W INTO THE CENTRAL GULF AND THE HIGH PRES TO THE NORTH MOVES FARTHER OFFSHORE. BIGGER QUESTIONS LIE OVER THE SOUTHERN BAHAMAS WHERE MOST OF THE MODELS ARE ALLOWING THE SURFACE TROUGH OVER THE BAHAMAS TO LINGER...WITH THE GFS...NAM...AND NOGAPS EVENTUALLY DEVELOPING A SURFACE LOW. ALL OF THE MODELS AGREE ON RELOADING THE ZONAL MID LEVEL TROUGHING OVER THE BAHAMAS WITH VORTICITY CURRENTLY ASSOCIATED WITH THE WEAKENING DEEP LAYER LOW OVER THE CENTRAL N ATLC. UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE RIDGE AXIS OVER THIS REGION AND TO THE EAST OF THE UPPER TROUGHING OVER THE GULF OF MEXICO SHOULD BE AN INGREDIENT FOR SIGNIFICANT CONVECTION HERE. THE FORECAST CALLS FOR AN INCREASED POSSIBILITY OF ENHANCED SURFACE TROUGHING IN THE REGION...WITH WINDS IN THE 20 TO 25 KT RANGE. CONFIDENCE REMAINS LOW IN THE DETAILS. RELIED PRIMARILY ON THE ECMWF FOR THE FORECAST. CARIBBEAN AND TROPICAL ATLC... ACCORDING TO THE 2230 QUIKSCAT PASS...0222 UTC ASCAT PASS...AND BUOY 42059...TRADES HAVE ONCE AGAIN RISEN ABOVE 20 KT OVER MUCH OF THE S CENTRAL CARIBBEAN. CONFIDENCE IN THE FORECAST IN THE CENTRAL AND EASTERN CARIBBEAN IS LOW AS THE PROJECTED WIND FIELD IS DIRECTLY TIED TO THE DEVELOPMENT...OR NON-DEVELOPMENT...OF A SURFACE LOW IN THE VICINITY OF THE SOUTHERN BAHAMAS. SEE DISCUSSION ABOVE. WITH THE ECMWF PREFERRED WITH THIS FEATURE... EXPECT LITTLE CHANGE IN THE 15 TO 20 KT E TO SE WINDS FORECAST OVER THE EASTERN/CENTRAL CARIBBEAN THROUGH SUN. LIGHT AND VARIABLE WINDS WILL CONTINUE TO BE THE STORY IN THE WESTERN CARIBBEAN WHERE FLOW HAS BEEN DISRUPTED BY THE LOW IN THE GULF OF MEXICO. FARTHER E OVER THE TROPICAL ATLC...TRADE WINDS SHOULD GRADUALLY BUMP BACK UP TO 20 KT AS THE PERSISTENT LOW IN THE CENTRAL N ATL BREAKS DOWN AND THE RIDGE BUILDS BACK IN TO THE N. WARNINGS ATLC... .GALE WARNING N OF 28N W OF 77W...AMZ080. CARIBBEAN... .NONE. GULF OF MEXICO... .GALE WARNING N OF 28N...GMZ086 AND GMZ084.. FORECASTER SCHAUER CLARK. TROPICAL PREDICTION CENTER.