000 FXUS66 KPQR 230449 AFDPQR AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PORTLAND OR 848 PM PST SUN NOV 22 2009 .SYNOPSIS...ISOLATED SHOWERS WILL CONTINUE TO DECREASE TONIGHT AS A WEAK UPPER RIDGE SHIFTS INTO OREGON. A WEAK WARM FRONT OFF THE COAST WILL SHIFT NORTHEAST ON MONDAY...THEN STALL OVER THE REGION ON TUESDAY. THE FRONT WILL FINALLY LIFT NORTH INTO WASHINGTON ON WEDNESDAY...BEFORE A COLD FRONT PUSHES SOUTHEAST INTO THE REGION LATE THURSDAY. && .SHORT TERM...SATELLITE IMAGERY AND METARS SHOW THE CLOUDS BREAKING UP OVER THE VALLEYS THIS EVENING...WHILE WEAKENING ONSHORE FLOW IS STILL ALLOWING SOME SHOWERS OVER THE MOUNTAINS. HOWEVER SATELLITE AND MODELS SUGGEST MID LEVEL CLOUDS AHEAD OF A WEAK WARM FRONT WILL ADVECT INTO THE REGION OVERNIGHT...BUT MODELS SHOWING NO QPF EXCEPT FOR A LITTLE RESIDUAL PRECIP OVER THE NORTHERN MOUNTAINS...AS WEAK SUBSIDENCE DEVELOPS AS A PRECURSOR UPPER RIDGE SHIFTS INLAND. ADDED SOME PATCHY VALLEY FOG FOR EARLY MON BUT THIS MIGHT NOT MATERIALIZE IF THE MID LEVEL CLOUDS ARE THICK ENOUGH. RW REMAINDER OF SHORT TERM UNCHANGED... AN AREA OF WARM AIR ADVECTION SETS UP OVER THE NW PART OF THE FORECAST AREA MON...AND CONTINUES INTO TUE. A WEAK SHORTWAVE MOVES ACROSS THE TOP OF THE DEVELOPING UPPER RIDGE TUE...BRINGING THE BEST CHANCE FOR OVERRUNNING PRECIPITATION TO THE NW PART OF THE AREA ON MON NIGHT WITH THE SHORT WAVE MOVING THROUGH THE FORECAST AREA WEDNESDAY. .LONG TERM...MODELS IN SOME AGREEMENT ON BRINGING A FRONTAL SYSTEM AND ITS ASSOCIATED UPPER LEVEL TROF THROUGH THE REGION THU/THU NIGHT FOR A RETURN TO WET WEATHER. AFTER THIS SYSTEM MOVES THROUGH...THE WEAK HIGH PRES RIDGE REASSERTS ITSELF OVER THE FORECAST AREA...KEEPING MOST ENERGY NORTH OF FORECAST AREA. && .AVIATION...CLOUDS AND SHOWERS CONTINUE TO DECREASE THIS EVENING AS HIGH PRESSURE BUILDS OVERHEAD. DESPITE RELATIVELY STRONG GRADIENTS THIS EVENING WINDS ACROSS MOST AREAS ARE CALM. WITH RECENT RAINS AND CLEARING SKIES AREAS OF IFR FOG MAY FORM IN FAVORED AREAS SUCH AS HILLSBORO AND THE SOUTH WILLAMETTE VALLEY AFTER 09Z...OTHERWISE EXPECT VFR CONDITIONS. THE NEXT SYSTEM WILL BEGIN TO MOVE IN MONDAY AFTERNOON WITH RAIN STARTING IN THE AFTERNOON ON THE COAST. KPDX AND APPROACHES...VFR CONDITIONS EXPECTED TONIGHT. HOWEVER... THERE IS A 30% CHANCE OF IFR FOG OR STRATUS BETWEEN 10Z AND 18Z. && .MARINE...LIGHT WINDS WILL CONTINUE TONIGHT. WINDS WILL INCREASE TO GALE FORCE BY LATE MONDAY MORNING ACROSS THE NORTHERN WATERS AND SMALL CRAFT ACROSS THE SOUTHERN WATERS. SEAS AT 15-18 FT THIS EVENING WILL DROP TONIGHT TO NEAR 11 FT BEFORE BUILDING BACK INTO THE MID TEENS ON MONDAY EVENING. && .PQR WATCHES/WARNINGS/ADVISORIES... WA/OR...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER TO FLORENCE THROUGH MONDAY MORNING. SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO CASCADE HEAD MONDAY MORNING. SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE MONDAY AND MONDAY EVENING. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR CONDITIONS THROUGH MON NIGHT. GALE WARNING FROM CAPE SHOALWATER TO CASCADE HEAD MONDAY THROUGH EARLY MONDAY EVENING. && $$ 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.