000 FXUS66 KPQR 290425 AFDPQR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FORECAST DISCUSSION NATIONAL WEATHER SERVICE PORTLAND OR 830 PM PST THU MAR 28 2002 .SYNOPSIS...A RIDGE OF HIGH PRESSURE ALOFT OVER THE EASTERN PACIFIC CONTINUES TO PUSH APPROACHING WEATHER SYSTEMS TO THE NORTH OF THE FORECAST AREA WITH ONLY SOME TRAILING CLOUDS AND SPOTTY LIGHT PRECIPITATION MAKING IT TO NORTHWEST OREGON. A SLIGHTLY STRONGER WEATHER SYSTEM WILL DIG FARTHER SOUTH INTO THE RIDGE ON SATURDAY NIGHT AND SUNDAY TO BRING A CHANCE OF RAIN TO NW OREGON AND SW WASHINGTON. THE RIDGE WILL QUICKLY REBUILD OVER THE AREA MON. BY THE MIDDLE OF NEXT WEEK TEMPERATURES SHOULD CLIMB WELL INTO THE 60S FOR A NICE PERIOD OF SPRING WEATHER. .DISCUSSION... .SHORT TERM...MOIST ONSHORE LOW LEVEL FLOW AND HIGH LEVEL MOISTURE RIDING THROUGH THE TOP OF THE PACIFIC RIDGE WILL CONTINUE NIGHT AND MORNING CLOUDS BUT BY TOMORROW AFTERNOON MODELS ADVERTISE A NORTHWARD SHIFT OF THE SURFACE RIDGE AXIS. THIS COUPLED WITH SLIGHTLY HIGHER HEIGHTS ALOFT SHOULD ALLOW MORE AFTERNOON CLEARING. THIS PATTERN OF MORNING CLOUDS AND AFTERNOON SUNSHINE SHOULD HOLD THROUGH SAT. BY SATURDAY NIGHT THE EXPECT A SLIGHTLY STRONGER UPPER LEVEL TROUGH TO DROP DOWN THE BRITISH COLUMBIA COAST AND DIG FARTHER SOUTH INTO THE UPPER RIDGE. THIS WILL BRING A CHANCE OF RAIN INTO THE FORECAST AREA SAT NIGHT AND SUN. .LONG TERM...AN EASTERN PAC RIDGE CONTINUES EARLY NEXT WEEK. BY TUE A THERMAL TROUGH WILL PUSH NORTHWARD UNDER THE RIDGE...ALONG THE OREGON COAST FOR OFFSHORE LOW LEVEL FLOW. THIS WILL DRAW A COOL AIR MASS ACROSS THE AREA MON AND TUE BUT MAY SEE SOME DOWNSLOPE WARMING AT THE COAST AND AS WINDS SLACK OFF WED AND THU HIGHER SPRINGTIME SUN ANGLES WILL BRING MORE SURFACE HEATING TO MODIFY THE LOW LEVEL AIR MASS FOR WARMER TEMPS. WILLSON AST 111146 PDX 110145 SLE 110035 EUG 000025 .PQR...SMALL CRAFT ADVISORY...CAPE SHOALWATER TO CASCADE HEAD FOR HAZARDOUS SEAS.