000 AGXX40 KNHC 211853 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 300 PM EDT FRI AUG 21 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... ATLC HIGH PRES RIDGE DRAPES OVER AND ACROSS THE TOP OF BILL AND THEN EXTENDS WEAKLY SE INTO GULF WATERS JUST ALONG 27/28N MAINTAINING A GENTLE BREEZE N OF 24N. HOWEVER...RETURN FLOW ACROSS SE GULF OF 20 KT WAS DEPICTED BY A MORNING QUIKSCAT PASS AND HAD TO UPDATE GLFMEX FCSTS. MODELS DID NOT INDICATE THIS NOR DO THEY INDICATE ANY CONTINUATION OF THIS...AND SHOW WINDS WEAKENING ACROSS THE FAR W AND SW GULF BY THIS EVENING. BILL WILL SPLIT THE RIDGE IN TWO AND LEAVE AN ELONGATED RIDGE ACROSS THE GULF NEXT FEW DAYS...WHICH WILL ALLOW FOR ELYS ACROSS THE SRN GULF AND A CHANCE FOR FRESHENING FLOW ACROSS THE SW GULF THIS WEEKEND. CARIBBEAN... BILL WILL DISCONNECT FROM THE CARIBBEAN AND ASSOCIATED MID LEVEL FLOW DURING THE NEXT 36 HOURS...AND ALL EASTERLY FLOW TO RETURN TO THE BASIN. CURRENTLY...WINDS WERE LESS THAN 20 KT ACROSS MOST OF THE BASIN...SAVE FOR ENHANCED FLOW THROUGH THE WINDWARD PASSAGE...IN THE LEE OF CUBA...AND A SMALL AREA ALONG THE COAST OF COLOMBIA...ALL DEPICTED BY MORNING QUIKSCAT PASS. POSITIVELY TILTED TROPICAL WAVE APPROACHING THE WINDWARDS THIS AFTERNOON WILL BRING A BROAD WIND SURGE INTO THE BASIN THIS WEEKEND...AS THE NRN VORT AND ASSOCIATED 30 KT MID LEVEL JET MOVE ACROSS THE CARIB N OF 14N. MODELS RESPOND BY BRINGING A 20-25 KT SURGE BEHIND THE NRN VORT AND ACROSS THE TOP OF THE SRN VORT S OF 13N...RAISING SEAS TO 9 FT...POSSIBLY HIGHER ACROSS THE E CENTRAL CARIB SUN...AND FRESHENING THE FLOW BASIN WIDE. SAL AND DRY AIR WITH THIS WIND SURGE WILL PROVIDE THE CHANCE FOR SQUALLS AND VERY GUSTY WINDS ALONG THE LEADING EDGE OF THIS WIND SURGE. SWELL ASSOCIATED WITH BILL HAS DIMINISHED...BUT WAS STILL MOVING THROUGH THE CARIB PASSAGES THIS MORNING...AND MORE NELY THAN YESTERDAY. STRONGEST SWELL ENERGY ACROSS THE BASIN FROM BILL LIKELY STILL MOVING THROUGH THE WINDWARD PASSAGE TO THE N COAST OF JAMAICA. ATLANTIC W OF 55W... HURCN BILL REMAINS AS MAIN FEATURE...NOT ONLY DUE TO ITS POWER AS CAT 3...BUT THE CONTINUED LARGE SIZE OF ITS WIND AND WAVE FIELD. BILL HAS WEAKENED DURING THE PAST 12 HOURS BUT WAS RECENTLY SHOWING IMPROVED STRUCTURE IN THE INNER CORE AND COULD RESTRENGTHEN A BIT NEXT 12-24 HOURS. TOO...BILL HAS TURNED SLIGHTLY RIGHT OF RECENT FORECASTS...AND STRONGEST SWELL ENERGY NOW IS BEING AIMED MORE TOWARDS EXTREME NRN NEW ENGLAND AND THE CANADIAN MARITIMES. SWELL FROM BILL ENERGY IS SLOWLY SUBSIDING S OF 22N THIS AFTERNOON...BUT IS NOW BEGINNING TO PEAK ACROSS THE BAHAMAS AT 12 FT AND GREATER...AND WILL GRADUALLY SPREAD NW AND W AND INTO FLORIDA DURING THE NEXT 12-24 HOURS. SWELL FORERUNNERS OF 18-20 SECONDS HAVE BEGUN TO HIT BUOY 41114 OFF OF FT PIERCE THIS AFTERNOON AND WILL BUILD SLOWLY THROUGH ABOUT MIDNIGHT ALONG THE FLORIDA COAST...AND THEN MORE QUICKLY OVERNIGHT INTO SAT...AND EXPECTED TO PEAK FROM JUST N OF PALM BEACH INTO GEORGIA AT 8-10 FT AT 13-14 SECONDS...WITH EVEN STRONGER ENERGY 12-16 FT AT 15-16 SECONDS INTO THE OUTER BANKS SATURDAY AFTERNOON AND EVENING. THIS WILL CREATE HUGE WAVES BY EAST COAST STANDARDS...BEACH AND COASTAL EROSION...AND VERY STRONG AND DEADLY RIP CURRENTS. WAVES OF THIS WAVE PERIOD WILL INITIALLY NOT BE CONDUCIVE FOR GOOD SURFING CONDITIONS AT MOST BREAKS...AS THIS WAVE LENGTH BREAKING ON SANDBARS WILL LIKELY CLOSE OUT. OUTER BARS AND OFFSHORE REEFS AND SHOALS WILL SEE BREAKING WAVES OF 14 TO 20 FT AND GREATER...AND SMALL CRAFT SHOULD EXERCISE EXTREME CAUTION ENTERING AND EXITING PORT AS SOME CHANNELS MAY BRIEFLY CLOSE OUT WITH LARGE WAVE ACTION. LIMITED SWELL ENERGY IS EXPECTED TO REFRACT ACROSS THE TOP OF THE NRN BAHAMAS AND GET INTO S FL INTO FT LAUDERDALE...LIKELY ONLY 3-4 FT...AND EVEN LESS LIKELY FOR SWELL ENERGY OF CONSEQUENCE TO BLEED THROUGH THE BAHAMAS AND GET INTO THE MIAMI DADE COUNTY WATERS. HIGH PRESSURE RIDGE AND A RETURN TO A BROAD ZONE OF FRESH NE TO E TRADES WILL BUILD INTO THE TROPICAL ATLC UNDERNEATH BILL...AND ENHANCE FLOW WITH AND ACROSS THE TOP OF THE NEXT FEW TROPICAL WAVES. MODEL GUIDANCE SHOWING STRONG LOW LEVEL JETS WITH THESE NEXT FEW WAVES. WARNINGS ATLC... HURRICANE WARNING N OF 25N E OF 72W...AMZ080. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE $$ FORECASTER STRIPLING