000 AGXX40 KNHC 251909 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 300 PM EDT WED AUG 25 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... W TO SWLY FLOW ALOFT ACROSS MAJORITY OF GULF CONTINUES TO ENHANCE TSTM CNVTN ALONG OLD STRUNG OUT BOUNDARY EXTENDING FROM CENTRAL FLORIDA TO 22N90W TO BAY OF CAMPECHE. BOUNDARY CONTINUES TO HANG ON AND HAS NOT DISSIPATED AS PER GFS FORECASTS FOR THE PAST SEVERAL DAYS. LLVL FLOW NOT STRONG ENOUGH TO KICK THIS BOUNDARY OUT OF THE BASIN AND WILL LIKELY LINGER BEYOND 24 HOURS. WEAK PRES PATTERN ACROSS THE GULF MAINTAINING LIGHT WINDS AND SLIGHT SEAS...AND NO SIGNIFICANT CHANGES EXPECTED IN NEXT FEW DAYS. CARIBBEAN AND THE TROPICAL N ATLC W OF 55W... NICE CYCLONIC CIRCULATION ASSOCIATED WITH SW CARIBBEAN TROPICAL WAVE NOW MOVING ACROSS CENTRAL AMERICA...WITH TRAILING BANDS OF SHOWERS AND TSTMS OFF HONDURAS AND NICARAGUA COASTS TO MOVE WNW AND PRODUCING SQUALLY AND GUSTY CONDITIONS THROUGH THIS EVENING. E TO SE FLOW OF 20-25 KT WITH GUSTS TO 30 KT BEHIND THIS WAVE IN THE FAR SW CARIB AND BEHIND THESE RAINBANDS WILL ENTER CENTRAL AMERICA OVERNIGHT AND LEAVE IMPROVING CONDITIONS ACROSS THE BASIN NEXT 24 HOURS...WITH THEN A RETURN TO MODERATE TO FRESH TRADES AND MODERATE SEAS FOR THIS TIME OF YEAR ACROSS THE BASIN. SW N ATLC... COMPLEX TROPICAL WAVE ACROSS THE SW N ATLC BETWEEN 60W AND 67W CONTINUES TO INTERACT WITH UPPER TROUGH AND PAIR OF VORTS TO ITS W...ALIGNED N TO S ALONG 67/68W...AND IS PRODUCING A BROAD AND ELONGATED AREA OF SCATTERED MODERATE TO DEEP CNVTN. SAHARAN AIR THAT HAS WRAPPED AROUND THE FAR W OF THE WAVE IS AIDING IN PRODUCING SQUALLS AND HUGE OUTFLOW BOUNDARIES W OF 68W RACING AWAY FROM THE WAVE. AN EVENING QUIKSCAT PASS YESTERDAY SHOWED SEVERAL NON RAIN FLAGGED VECTORS WITH GREATER THAN 34 KT WINDS OCCURRING WITHIN AND TO THE N OF THIS BROAD AREA OF CNVTN...BUT THERE WERE NO MORNING SCATTEROMETER PASSES TODAY TO ASSIST. REGARDLESS...GALE FORCE WINDS ARE LIKELY OCCURRING IN A NARROW BAND ACROSS THE NRN SEMICIRCLE OF THE BROAD LLVL TROUGHING ASSOCIATED WITH THIS WAVE AND IS EXPECTED TO PERSIST WITH IT THROUGH 48 HOURS BEFORE WEAKENING. ACCOMPANYING SEAS ARE LIKELY IN EXCESS OF 15 FT NOW AND SHOULD BUILD IN A DYNAMIC FETCH TO AROUND 18 FT NEXT 24-36 HOURS. WE STILL PREFER A SOLUTION FOR THE MOVEMENT OF THIS FEATURE MORE TOWARD THE WNW AS PER RECENT ECMWF FORECASTS...THROUGH 48 HOURS...BEFORE TURNING MORE NW 48-72 HOURS. THE MORNING STLT PRESENTATION SUGGESTED A SFC LOW TRYING TO DEVELOP ACROSS WRN PORTIONS OF THIS WAVE...WHEREAS GLOBAL MODEL GUIDANCE WAS UNANIMOUS IN TRYING TO DEVELOP A LOW ACROSS THE SE PORTION OF THE WAVE THE PAST FEW DAYS. THIS ALSO MOVES US TOWARD A MORE WNW MOTION. STLT IMAGERY DOES NOT LOOK AS GOOD THIS AFTERNOON WITH LESS ORGANIZATION...AND AN ELONGATED AREA OF CNVTN...LIKELY COINCIDENT WITH THE WIND AND WAVE FIELD. THIS BROAD AREA OF 20-25 KT WINDS...AND NARROW BAND OF 30-35 KT WINDS AND SEAS IN EXCESS OF 12 FT WILL SLIDE WNW THROUGH LATE WED AND MAINTAIN VERY ROUGH CONDITIONS. WWIII GUIDANCE FOLLOWS THE GFS WIND FIELD...WITH BOTH OF THESE MODELS PRODUCING HIGHEST WINDS AND SEAS 3-8 DEGREES NE OF OUR POSITIONS. THIS SYSTEM SHOULD LIFT OUT OF THE AREA FRIDAY...WITH HIGH PRES BRIEFLY BUILDING INTO THE AREA AHEAD OF THE NEXT LARGE TROPICAL WAVE. REFER TO LATEST TROPICAL WEATHER OUTLOOK...MIATWOAT...FROM NHC ON THIS EVOLVING TROPICAL WAVE...AS WELL AS THE HIGH SEAS FORECASTS FROM TAFB...MIAHSFAT2. WARNINGS ATLC... .GALE WARNING N OF 22N FROM 63W TO 73W... .GALE WARNING EXPECTED WED AND WED NIGHT WITHIN 180 NM NE OF LOW PRES CENTER... CARIBBEAN... .NONE. GULF OF MEXICO... .NONE $$ FORECASTER STRIPLING