000 WWUS86 KSEW 211805 SABWA Northwest Weather and Avalanche Center Seattle Washington 931 AM PST Sat Nov 21 2009 In order to provide a better and more complete avalanche forecast on a regular basis, the primary avalanche forecasts will be issued between 11 AM and Noon on a daily basis, with updates issued whenever significant deviations occur. The timing and the products will be adjusted as necessary during the upcoming winter in order to produce the best possible avalanche information. WAZ-513-518-519-018-042-501-502 Avalanche Forecast OLYMPICS- WASHINGTON CASCADES NEAR AND WEST OF THE CREST- Saturday morning: Considerable avalanche danger above 4 to 5000 feet and moderate below briefly decreasing. Saturday afternoon, Saturday night and Sunday morning: Gradually increasing avalanche danger Saturday afternoon and significantly increasing danger Saturday night into Sunday morning becoming high above 5000 feet and considerable below. Sunday afternoon and night: Slowly decreasing avalanche danger becoming considerable above 4 to 5000 feet and moderate below WASHINGTON CASCADES EAST OF THE CREST...CORRECTED Saturday morning: Considerable avalanche danger above 6000 feet and moderate below briefly decreasing. Saturday afternoon and night: Slowly increasing avalanche danger Saturday afternoon and significantly increasing danger Saturday night becoming considerable above 5000 feet and moderate below, with greatest danger on lee slopes in higher terrain near the crest. Sunday: Little change in the danger Sunday morning but slowly decreasing danger Sunday afternoon and night, becoming considerable above 6000 feet and moderate below Snowpack Synopsis Following strong warming and significant avalanche activity on Thursday, and a slight decrease in the danger early Friday, further moderate to heavy snowfall and strong winds at lowering freezing levels mid-late Friday into early Saturday have produced another increase in the avalanche danger. Less new snow along the Cascade east slopes has helped to produce a generally lower danger overall. However, some new unstable wind slabs still exist on lee terrain at higher elevations, especially near the crest where heaviest snowfall was received. Saturday morning Briefly decreasing winds and light to occasionally moderate snow showers should allow for a brief and slight decrease in the avalanche danger. Saturday afternoon, Saturday night and Sunday morning Increasing light to moderate snow should spread southward Saturday afternoon becoming moderate to heavy later Saturday into early Sunday. Along with only slight warming, mainly in the south, and increasingly strong winds, this should produce a significant increase in the danger with high danger likely developing above about 5 to 6000 feet and considerable danger below. As a result, back country travel on steeper lee terrain is not recommended Sunday morning, especially at higher elevations. Sunday afternoon and night Moderate to heavy snow showers should slowly decrease Sunday afternoon and night. Along with continued low freezing levels and gradually diminishing winds this should allow for a slow decrease in the danger. However, despite the improving weather trend, back country travelers should continue to use extra caution on steeper lee slopes. NWAC weather data and forecasts are also available by calling 206-526-6677 for Washington, 503-808-2400 for the Mt Hood area, or by visiting our Web site at [1]www.nwac.us. Remember that these avalanche forecasts apply to back country avalanche terrain below 7000 feet outside of developed and operating ski areas or highways. Moore/Northwest Weather and Avalanche Center Seattle Washington References 1. file://localhost/..//