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000 FXUS62 KMFL 241835 AFDMFL AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIAMI FL 235 PM EDT WED SEP 24 2008 .DISCUSSION... SCATTERED SHOWERS...SOME WITH HEAVY RAINFALL CONTINUE TO PUSH SLOWLY SOUTHWEST ACROSS SOUTH FLORIDA EARLY THIS AFTERNOON. THESE SHOWERS ARE BEING DRIVEN BY STRONG NORTHEAST WINDS JUST NORTH OF THE LOCAL AREA ALONG THE EAST CENTRAL FLORIDA COAST AND ADJACENT COASTAL WATERS WHICH ARE CONVERGING WITH WEAKER WINDS ACROSS THE LOCAL AREA AS THE STRONG NORTHEAST FLOW HAS FAILED TO MAKE MUCH HEADWAY INTO SOUTH FLORIDA. MODELS SEEM TO HAVE HAD DIFFICULTY IN HANDLING THE EVOLUTION OF THIS PATTERN AS CAN BE EXPECTED WITH A COMPLEX SYSTEM OFF THE CAROLINAS. AS A RESULT I`VE GONE SLIGHTLY ABOVE GUIDANCE FOR RAIN CHANCES TONIGHT AS AT LEAST SOME ONSHORE COMPONENT TO THE LOW LEVEL FLOW WILL REMAIN THIS EVENING BEFORE A DRAINAGE WIND SETS UP OVERNIGHT CREATING CONVERGENCE ALONG THE EAST COAST...WHICH COULD LEAD TO MORE SHOWER GENERATION. WESTERN AREAS SHOULD DRY OUT BY THIS EVENING WITH MORE STABILITY TAKING HOLD AND DRIER AIR FILTERING IN FROM THE NORTH IN THE LOW LEVELS. TEMPS WILL BE SLIGHTLY COOLER TONIGHT ESPECIALLY ACROSS THE INTERIOR...WITH LOWS IN THE MID TO UPPER 60S VERSUS LOWER 70S ACROSS THE EAST COAST METRO AREAS. FOR THURSDAY AND FRIDAY...LIGHT WINDS AND PARTLY CLOUDY SKIES WILL BEGIN THE DAYS...BUT MODELS NOW SUGGEST SOME LOW-LEVEL MOISTURE WILL REMAIN ACROSS SOUTHERN AREAS. THIS COULD COMBINE WITH A WEAK AFTERNOON SEA BREEZE TO SET OFF AN ISOLATED SHOWER OR TWO DESPITE INCREASING MID-LEVEL SUBSIDENCE. NORTHWEST INTERIOR AREAS AS WELL AS COLLIER COUNTY MAY REMAIN DRY AS THE STRONGEST PUSH OF DRY AIR IMPACTS THESE LOCATIONS...WITH DEWPOINTS MIXING DOWN THROUGH THE 60S WHICH WILL BE A NICE BREAK FROM THE HUMIDITY...WITH EVEN SOME SUBTLE BUT NOTICEABLY LOWER HUMIDITY LEVELS ACROSS THE EAST COAST. LOW TEMPS COULD DIP INTO THE LOWER 60S ACROSS SOME OF THE NORMALLY COOLER NORTHWEST INTERIOR AREAS THURSDAY AND FRIDAY NIGHTS...WITH LOWER IN THE UPPER 60S TO AROUND 70 ACROSS THE EAST COAST METRO AND NAPLES AREAS. THE GFS HAS CHANGED SOME ON THE 12Z RUN THIS MORNING...MOVING DEEP-LAYERED MOISTURE AND THE REMNANT SURFACE TROUGH BACK NORTH THROUGH THE REGION A LITTLE QUICKER SATURDAY AND SUNDAY WITH INCREASING RAIN CHANCES. WILL NOT MAKE MANY ADJUSTMENTS TO THE WEEKEND FORECAST JUST YET AS THIS IS THE FIRST HINT OF THIS. MODERATE SWELLS WITH LARGE BREAKERS CAN BE SEEN ALONG THE NORTHERN PALM BEACH COAST AT JUPITER INLET EARLY THIS AFTERNOON WITH AN INCREASE NOTED THROUGH THE DAY SO FAR. UPSTREAM OBS SHOW 10FT/12S SWELLS AT BUOYS 41009 AND 41010 WHICH HAVE BEEN PRETTY STEADY THROUGH THE DAY. THIS SHOULD LEAD TO PEAK SWELLS BETWEEN 5 AND 6FT TONIGHT AND TOMORROW ALONG COASTAL PALM BEACH COUNTY BEFORE DECREASING TOMORROW NIGHT. SOME MINOR COASTAL FLOODING WILL BE POSSIBLE AT THE HIGH TIDE CYCLES ESPECIALLY AROUND 5AM TOMORROW MORNING AND BEACH EROSION IS POSSIBLE ESPECIALLY IN AREAS MADE VULNERABLE BY SWELL EVENTS THE PAST FEW YEARS. CURRENT FORECAST AND HIGH SURF ADVISORY REFLECT THE CURRENT AND EXPECTED CONDITIONS WELL. && .MARINE... NO CHANGES TO THE MARINE FORECAST IN THE SHORT TERM. WINDS CONTINUE TO BLOW AROUND 20KTS SUSTAINED ON LAKE OKEECHOBEE WITH HIGHER GUSTS ESPECIALLY IN RAIN. CURRENT FORECAST HAS SEAS PEAKING AROUND 10-11FT ACROSS THE GULF STREAM OFFSHORE PALM BEACH COUNTY LATE TONIGHT/TOMORROW AND GIVEN CURRENT UPSTREAM TRENDS AND WAVE WATCH GUIDANCE WHICH HAS BEEN VERY CONSISTENT AND ACCURATE SO FAR THIS SEEMS REASONABLE. FOR FRIDAY AND SATURDAY...I SLOWED THE RATE OF DECAY IN THE SEAS SOME AS WAVE WATCH SHOWS SWELLS LINGERING A BIT LONGER ESPECIALLY ACROSS THE NORTHERN ATLANTIC WATERS. && .FIRE WEATHER... DEWPOINTS SHOULD DECREASE TOMORROW AND LINGER IN THE LOWER 60S ACROSS NORTHWEST INTERIOR SECTIONS INTO FRIDAY AFTERNOON. THIS COULD LEAD TO RH`S DROPPING TO AROUND 40 PERCENT FOR AN HOUR OR TWO AROUND PEAK HEATING...BUT IF EVEN DRIER AIR CAN MIX DOWN FROM JUST ABOVE THE SURFACE THEN RH`S COULD DROP TO SLIGHTLY LOWER LEVELS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 73 87 67 87 / 20 10 10 10 FORT LAUDERDALE 76 87 70 87 / 20 10 10 10 MIAMI 75 87 71 86 / 20 10 10 10 NAPLES 72 86 67 88 / 10 10 10 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...HIGH SURF ADVISORY UNTIL 8 AM EDT FRIDAY FOR FLZ168. AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 AM EDT FRIDAY FOR AMZ650-AMZ651-AMZ670-AMZ671. SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR AMZ610. GM...NONE. && $$ DISCUSSION/MARINE/FIRE WX...STRASSBERG SHORT TERM/AVIATION...GREGORIA