000 FXUS66 KPQR 092145 AFDPQR AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PORTLAND OR 300 PM PDT FRI MAY 9 2008 .SYNOPSIS...WEAK HIGH PRES IS BRINGING MOSTLY CLEAR SKIES TO THE REGION THIS AFTERNOON. A WEAK FRONT WILL ARRIVE LATE SATURDAY...WITH UNSETTLED WEATHER CONTINUING INTO SUNDAY...BUT NOT A LOT OF RAIN IS EXPECTED. HIGH PRESSURE WILL BUILD NEXT WEEK BRINGING WARMER CONDITIONS. && .SHORT TERM...VISIBLE SATELLITE IMAGERY SHOWS MOSTLY CLEAR SKIES OVER ALL BUT THE EXTREME NW ZONES THIS AFTERNOON UNDER WEAK HIGH PRESSURE. SATELLITE IMAGERY SHOWS THE NEXT FRONT CURRENTLY OUT ALONG 134W. MODELS ARE IN BETTER AGREEMENT ON THE TIMING OF THIS SYSTEM...BRINGING A SLIGHT CHANCE OF PRECIPITATION OVER NORTHWEST ZONES SAT...WITH THE WEAKENING FRONT MOVING ONSHORE SAT EVENING WITH A BETTER CHANCE OF RAIN. SNOW LEVELS REMAIN ABOVE MAJOR PASSES IN CASCADES THROUGH SAT EVENING...AND NOT ENOUGH PRECIPITATION TO CREATE ANY SNOW ISSUES IN THE CASCADES. THE ASSOCIATED UPPER LEVEL TROUGH OF LOW PRESSURE WILL MOVE EAST OF THE AREA LATE SUN WITH SHOWERS DIMINISHING SUN NIGHT. MODELS BEGIN BUILDING SOME WEAK RIDGING OVER THE AREA MONDAY WITH SYSTEMS DEFLECTING TO THE NORTH. MODELS CONTINUE TO KEEP PRECIPITATION ASSOCIATED WITH THE MON WARM FRONT OVER THE WATERS...WITH NO PRECIPITATION OVER THE INTERIOR. LIKENS .LONG TERM...MODELS CONTINUE TO SHOW STRONG RIDGING OVER THE FORECAST AREA FOR THE EXTENDED PERIOD. ONLY EXCEPTION TO THE DRY FORECAST WILL BE TUE/TUE NIGHT AS A FRONTAL SYSTEM IS DEFLECTED NORTH OF OUR AREA. THE MAIN EFFECT WILL BE AN INCREASE IN CLOUDS OVER NORTHERN ZONES AND A SLIGHT CHANCE OF PRECIPITATION OVER THE EXTREME NORTHERN ZONES. OTHERWISE WILL KEEP THE FORECAST DRY THROUGH FRIDAY. EXPECT A NICE WARMING TREND WITH THU BEING THE WARMEST DAY...WITH MAX TEMPERATURES IN THE MID 80S INLAND. THE WARMING WILL BE SHORT-LIVED THOUGH AS THE THERMAL TROUGH SHIFTS INLAND THU NIGHT. FRI WILL SEE COOLER TEMPERATURES...ESPECIALLY ALONG THE COAST IN AN INCREASING ONSHORE FLOW. EXPECT MARINE CLOUDS TO PUSH ONSHORE LATE FRI. && .AVIATION...VFR CONDITIONS ACROSS THE ARE THIS AFTERNOON AND TONIGHT AS HIGH PRESSURE MOVES ACROSS THE AREA. A WEAKENING FRONTAL SYSTEM WILL APPROACH LATER TONIGHT WITH MVFR CIGS AND A CHANCE OF LIGHT RAIN SPREADING INTO THE N COAST BY 12Z. VFR CIGS EXPECTED INLAND SAT MORNING WITH SOME LOCAL MVFR CONDITIONS AND DEVELOPING INLAND DURING THE AFTERNOON WITH CHANCE OF RAIN. KPDX AND APPROACHES...VFR THIS EVENING. MVFR CIGS POSSIBLE BY 22Z && .MARINE...HIGH PRESSURE WILL GIVE WAY TO APPROACHING WEAKENING FRONTAL SYSTEM TONIGHT. WINDS WILL SHIFT TO THE SOUTH AND INCREASE SATURDAY AS FRONT APPROACHES. MAY SEE A FEW GUSTS NEAR SMALL CRAFT ADVISORY CATEGORY SATURDAY AFTERNOON JUST AHEAD OF FRONT BUT NOT FREQUENT ENOUGH TO WARRANT ADVISORY. SWELL EXPECTED TO INCREASE SAT NIGHT AND SUNDAY FROM A SLOW MOVING LOW IN THE GULF OF ALASKA. CURRENTLY EXPECT SWELL TO REMAIN JUST BELOW ADVISORY LEVELS. THE COLUMBIA RIVER BAR WILL SEE THE LAST STRONG EBB FOR A WHILE SATURDAY MORNING. DONT EXPECT THE HIGHER SWELL TO REACH THE BAR BY THAT TIME SO WILL SEAS ON THE BAR SHOULD BE JUST BELOW ADVISORY LEVELS. HIGH BUILDS BEHIND FRONT FOR NW FLOW TOMORROW NIGHT AND SUN. HIGH MOVES OVER THE AREA MON FOR LIGHTER WINDS. THERMAL TROUGH SHOULD DEVELOP IN THE SOUTH BY WEDNESDAY AND SHIFT NORTH ON THURSDAY RESULTING IN INCREASING NW WINDS. && .PQR WATCHES/WARNINGS/ADVISORIES... WA/OR...NONE. && .PRELIMINARY POINT POPS (PROBABILITY OF MEASURABLE PRECIPITATION) AST 035321 PDX 014321 SLE 014321 EUG 013321 $$ 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.