000 AGXX40 KNHC 290754 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 300 AM EDT WED APR 29 2009 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... WINDS HAVE BEGUN TO RELAX ACROSS ALL BUT S AND SE PORTIONS PAST 8 HOURS AS LONG WAVE TROUGH AND MAJOR FRONTAL SYSTEM HAS MOVED ACROSS THE ROCKIES AND IS APPROACHING THE CENTRAL PLAINS...WHILE UPSTREAM RIDGING HAS BEGUN TO NUDGE ATLC HIGH PRES RIDGE NORTHEASTWARD. IN ADDITION...A WEAK INVERTED TROUGH HAS BECOME APPARENT FROM THE YUCATAN...NE INTO THE ERN GULF AND HAS ACTUALLY HELPED TO INCREASE THE PRES GRADIENT ACROSS THE E CENTRAL GULF A BIT FROM 24 HOURS AGO. 20-25 KT ELY WINDS PERSISTED THROUGH THE FLORIDA STRAITS THIS EVENING PER SCATTEROMETER WINDS...WITH ATYPICAL HIGH AND STEEP SEAS IN EXCESS OF 10 FT PERSISTING WITHIN THE FLORIDA CURRENT THERE. ALSO...NELY 20-25 KT FLOW AROUND THE NW CORNER OF THE YUCATAN PERSISTED AS WELL. BOTH OF THESE AREAS CONTINUE TO BE UNDERDONE BY WW3 MODEL. AREAL EXTENT OF 20 KT WINDS AND GREATER HAS SHRUNKEN...WITH THIS DOWNWARD TREND EXPECTED TO CONTINUE THROUGH THU. HOWEVER...20 KT ELY WIND FLOW IS LIKELY TO CONTINUE THROUGH THE STRAITS OF FLORIDA AND ACROSS THE SW GULF S OF 23N DURING THIS TIME. THE W ATLC HIGH PRES CENTER WILL WEAKEN FURTHER THROUGH WED AND DRIFT E...RELAXING THE PRES GRADIENT OVER ALL BASINS AND ALLOWING WINDS TO DIMINISH. SW N ATLC... A WEAKENED 1029 MB HIGH JUST N OF AREA CONTINUES TO FORCE A BROAD SWATH OF 20 KT NE-E WINDS ACROSS THE BASIN S OF 25-26N...WITH POCKETS OF 25 KT W OF 70W. THIS FLOW CONTINUES TO FUNNEL THROUGH THE STRAITS OF FLORIDA AND INTO SE GULF AND WINDWARD PASSAGE. A LONG NELY FETCH ACROSS THE TROPICAL AND SUBTROPICAL ATLC INDUCED BY THE ATLC HIGH PRES RIDGE OF THE PAST SEVERAL DAYS HAS CONTINUED TO GENERATE MODERATE PERIOD WIND SWELL INTO BAHAMAS AND GREATER ANTILLES...PRODUCING ROUGH AND STEEP SEAS UPWIND AND THROUGH PASSAGES BETWEEN ISLANDS. BOTH WINDS AND SEAS HAVE PEAKED ACROSS THE REGION AS THE HIGH AS BEGUN TO WEAKEN AS FORECAST...AND AREAL EXTENT OF 20-25 KT WINDS IS SHRINKING. PEAK SEAS OF 9-10 FT MOVING INTO EAST COASTS OF THE BAHAMAS WILL SLOWLY SUBSIDE NEXT FEW DAYS. GUIDANCE CONTINUES TO INDICATE THE W ATLC HIGH WEAKENING AND MOVING NE LATE TODAY THROUGH THU...HENCE RELAXING PRES GRADIENT AND DIMINISHING WINDS AND SEAS. CARIBBEAN AND TROPICAL N ATLC... EVENING SCATTEROMETER PASSES CONTINUED TO SHOW 20-25 KT E TO NE FLOW ACROSS MOST OF THE CARIBBEAN...WITH WINDS TO 30 KT OFF THE COAST OF COLOMBIA. A RELAXED GRADIENT IN THE FAR NW CARIB DUE TO YUCATAN TROUGH HAS DIMINISHED WINDS SOMEWHAT THERE. AS THE W ATLC HIGH WEAKENS AND DRIFTS NE DURING THE NEXT 48 HOURS...WINDS AND SEAS WILL FOLLOW SUIT ACROSS THE CARIBBEAN AS WELL...INTO THE 15-20 KT RANGE ACROSS MOST OF THE BASIN THU-FRI...WITH SUSTAINED 20 KT FLOW LIKELY ALONG THE SRN AND CENTRAL CARIB. ATLC... .NONE.. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FORECASTER STRIPLING. TROPICAL PREDICTION CENTER.