FXUS66 KPQR 042231 AFDPQR AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PORTLAND OR 230 PM PST WED DEC 3 2008 .SYNOPSIS...A STRONG RIDGE OF HIGH PRESSURE IS BRINGING DRY WEATHER TO THE FORECAST AREA TODAY. DRY WEATHER WILL CONTINUE THROUGH SATURDAY. A WEAK PACIFIC FRONTAL SYSTEM WILL BRING SOME RAIN BACK TO THE FORECAST AREA SATURDAY NIGHT AND SUNDAY. MORE FRONTAL SYSTEMS WILL AFFECT THE AREA THROUGH THE MIDDLE OF NEXT WEEK. && .SHORT TERM...SATELLITE IMAGERY SHOWS THAT THE STRONG OFFSHORE SURFACE GRADIENT HAS HELPED TO BRING CLEAR SKIES TO THE ENTIRE FORECAST AREA THIS AFTERNOON. EASTERLY SURFACE WINDS ARE GUSTING IN THE 30S THROUGH THE COLUMBIA RIVER GORGE AND ACROSS THE MOUNTAINS. AN UPPER LEVEL HIGH PRESSURE AREA NOSES INTO WESTERN ORE FRI. OFFSHORE FLOW WILL BE WEAK ON FRI WITH SOME EAST WINDS NEAR THE GORGE BUT THE AREAS AWAY FROM THE GORGE WILL HAVE VERY LIGHT WINDS WHICH WILL ALLOW FOG/STRATUS TO REMAIN IN THE SOUTHERN VALLEY AND MORE EXTENSIVE FOG AND STRATUS THROUGHOUT THE VALLEY FRIDAY NIGHT AND SATURDAY. MODELS HAVE CONTINUED TO SLOW DOWN THE PROGRESS OF THE NEXT FRONTAL SYSTEM. CURRENT MODELS HAVE THE PRECIPITATION AHEAD OF THE FRONT NOT REACHING OUR COAST UNTIL LATE SAT AFTERNOON AND SPREADING INTO THE REMAINDER OF THE FORECAST AREA LATE SAT NIGHT. LIKENS .LONG TERM...A WEAK COLD FRONT WILL MOVE THROUGH THE AREA SUN...FLATTENING THE UPPER LEVEL RIDGE. THIS FEATURE DESTABILIZES THE ATMOSPHERE BRINGING COOL SHOWERY WEATHER AS WELL AS TRIGGERING A STRONG PUSH OF MARINE AIR. THE WEATHER PATTERN TURNS MORE ACTIVE NEXT WEEK AS THE JET STREAM STARTS MIGRATING SOUTHWARD. A PACIFIC FRONTAL SYSTEM IS EXPECTED MON NIGHT/TUE...HOWEVER THE EXACT TIMING IS STILL UNCERTAIN. MODELS DIVERGE SIGNIFICANTLY BY DAY SEVEN AND WILL GO WITH PERSISTENCE AT THIS TIME. && .AVIATION...THE ENTIRE FORECAST AREA IS BASICALLY CLEAR AS OFFSHORE FLOW HAS CLEARED OUT ALL THE FOG AND LOW STRATUS OUT. WILL PROBABLY SEE SO LOCAL IFR RETURN IN THE SOUTHERN WILLAMETTE VALLEY AND POSSIBLY NORTH OF KKLS BUT DUE TO WARMING UP AND DRYING OUT DURING THE DAY TODAY EXPECT FORMATION TO BE RATHER LATE. ONCE IT FORMS NEAR KEUG TONIGHT...MAY BE A BIT SLOW TO CLEAR FRIDAY AFTERNOON DUE TO LIGHT GRADIENTS. ANYTHING AT THE COAST WILL BE VERY PATCHY LATE TONIGHT AND FRIDAY MORNING. KPDX AND APPROACHES...VFR TONIGHT AND FRIDAY WITH EAST WINDS TO 30 KT OR SO TOWARDS KTTD...LESS TOWARD KHIO...WEAKENING LATER TONIGHT AND FRIDAY. POSSIBLY SOME PATCHY IFR LATE TONIGHT AND EARLY FRIDAY WESTERN APPROACHES NEAR KHIO BUT THIS IS NOT CERTAIN. TOLLESON && .MARINE...STILL DEALING WITH SOME LONGER PERIOD SWELL THOUGH PERIODS EASING BACK TO 15 TO 16 SECONDS AND WILL CONTINUE TO SHORTEN TO 12 SECONDS FRIDAY. SEAS 12 FT AT BUOY 89 WILL KEEP SEAS AROUND 10 FT OR MORE IN OUR WATERS FOR AWHILE TONIGHT. WINDS MARGINAL BUT WILL KEEP A SMALL CRAFT ADVISORY FOR THE EVENING FOR EASTERLY GAP WINDS IN THE INNER WATERS AND A LITTLE MORE NORTHERLY IN THE SOUTHERN OUTER WATERS. WINDS QUITE LIGHT FRIDAY. A WEAK FRONT OVER THE WEEKEND MAY BRING SOUTH WINDS UP CLOSE TO SMALL CRAFT LEVELS. TOLLESON && .PQR WATCHES/WARNINGS/ADVISORIES... OR/WA...SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR THIS EVENING. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER TO FLORENCE THROUGH THIS EVENING. SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO FLORENCE OUT 20 NM THROUGH EARLY TONIGHT. SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE 20 TO 60 NM OFFSHORE THROUGH EARLY TONIGHT. && $$ MORE WEATHER INFORMATION ONLINE AT... Http://weather.gov/portland THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.