130 PM PST SAT FEB 16 2008 WEATHER SYNOPSIS FOR SATURDAY AND SUNDAY A weak upper trough and associated frontal band passed from northwest to southeast across the area Friday evening. This system brought a bit of rain or wet snow initially with gradual cooling overnight. The weak disturbance did not produce any precipitation over the Mt Hood area with only very light amounts in the south Cascades. Precipitation ended early Saturday with a few light showers persisting in the Snoqualmie Pass area through mid morning. High pressure is gradually building into the region with skies clearing out in many areas Saturday afternoon. Freezing levels are remaining relatively low Saturday in the wake of the earlier trough passage before really rising over the next few days. An upper level ridge in the eastern Pacific is strengthening and building towards the Pacific Northwest coast. Moderate northwest flow on the eastern side of the ridge should maintain northwest flow aloft over the area Saturday. By Sunday the ridge should move nearer the coast to allow for weak low level offshore flow and weak north to northeast flow aloft. This should cause mostly fair skies Sunday and significantly rising freezing levels. Freezing levels should reach 11,000 feet by Sunday afternoon from the north Washington Cascades to Mt Hood for our warmest conditions of the season. Similar conditions are expected in the mountains Monday, warm and sunny! WEATHER FORECAST FOR SATURDAY AND SUNDAY * OLYMPICS- Saturday aft and night: Becoming partly cloudy with mainly high clouds. Sunday: Sunny and very warm. Sunday night: Fair skies and warm overnight. * WASHINGTON CASCADES NEAR AND WEST OF THE CREST- * CASCADE PASSES INCLUDING STEVENS, SNOQUALMIE AND WHITE PASSES- Saturday afternoon and night: Becoming partly sunny afternoon hours and partly cloudy overnight with mainly high clouds. Sunday: Sunny and very warm. Sunday night: Fair skies and warm overnight. * EAST SLOPES WASHINGTON CASCADES- Saturday afternoon and night: Partly cloudy with mainly high clouds and some areas of low clouds or fog lower elevations and valleys. Sunday: Sunny and very warm. Sunday night: Fair skies and warm overnight. * MT HOOD AREA- Saturday afternoon and night: Mostly sunny afternoon and fair overnight. Sunday: Sunny and very warm. Sunday night: Fair skies and warm overnight. FREEZING LEVELS-CASCADE MTNS 3500 ft N and C, 7500 ft S Saturday afternoon 6000 ft N, 9000 ft S Saturday night 8500 ft N, 10,500 ft S Sunday morning 10,500 ft N, 11,500 ft S Sunday aft and night FREEZING LEVELS-OLYMPIC MTNS 4000 ft Saturday afternoon 8000 ft Saturday night 10,000 ft Sunday morning 11,500 ft Sunday aft and night Cascade Snow/Freezing Levels refer to the northern Washington Cascades (N) through Mt Hood area (S). Central Washington Cascade snow levels (typically near Snoqualmie Pass) are normally midway between indicated N and S levels. Note that surface snow/freezing levels are common near the passes during easterly pass flow and may result in multiple snow/freezing levels. 24 HOUR FORECAST OF PRECIPITATION IN INCHES OF WATER EQUIVALENT ENDING AT 4AM SUN MON * HURRICANE RIDGE 0 0 * MT BAKER 0 0 * WASHINGTON PASS 0 0 * STEVENS PASS 0 0 * SNOQUALMIE PASS LT .10 0 * MISSION RIDGE 0 0 * CRYSTAL MTN LT .10 0 * PARADISE LT .10 0 * WHITE PASS 0 0 * MT HOOD 0 0 WINDS IN MILES PER HOUR (MPH) * CASCADE PASS LEVEL WINDS W 5-15 Saturday afternoon E 0-10 Saturday night E 5-15 Sunday and Sunday night * FREE WINDS AT 5000 FT NW 10-20 Saturday aft and eve N-NE 5-15 Saturday night E 5-15 Sunday morning E 5-15 N and C, E 15-25 S Sunday aft E-SE 5-15 Sunday night * FREE WINDS AT 9000 FT NW 20-30 Saturday aft and eve N 15-25 Saturday night and Sunday morning N-NE 5-15 Sunday aft E 5-15 Sunday night EXTENDED WEATHER SYNOPSIS FOR MONDAY THROUGH WEDNESDAY The strong upper level ridge should cross the Cascades Monday. This should allow for continued sunny and very warm weather Monday. Easterly surface flow across the passes should maintain a weak inversion but still mild temperatures at the passes as well Monday. A weakening and splitting frontal system should move across the area late Tuesday and early Wednesday to cause a little light precipitation at lowering freezing levels and moderate but increasing winds. Clouds should increase Tuesday with a light rain or snow Tuesday night. Some light to moderate precipitation is expected early Wednesday and showers Wednesday night. EXTENDED FORECAST FOR MONDAY THROUGH WEDNESDAY Monday: Mostly sunny days and fair nights and warm. Early Tuesday: Increasing mid and high clouds. Late Tuesday: Light rain or snow at times. Wednesday: Light to moderate rain or snow early changing to light showers late. * FREEZING LEVELS 9-11,000 ft N, 10-12,000 ft S Monday morning 6-8000 ft N, 7-9000 ft C, 8-10,000 ft S Monday afternoon and night, except locally cooler near the Cascade passes Monday * SNOW LEVELS 4-6000 ft N, 5-7000 ft S early Tuesday 2-4000 ft N, 3-5000 ft S late Tuesday and Wednesday