830 AM PST Saturday, March 06, 2004 ********************************************************** ZONE AVALANCHE FORECASTS..... WASHINGTON CASCADES NEAR AND WEST OF THE CREST... AVALANCHE WATCH FOR SUNDAY.... Considerable avalanche danger above 4000 feet and moderate below Saturday. Locally increased danger Saturday on slopes receiving sunshine, especially during the afternoon. Significantly increasing danger expected late Saturday night and early Sunday becoming high to extreme above 5000 feet and high below. Danger gradually decreasing late Sunday becoming considerable above 5000 feet and moderate below. NOTE: Natural avalanches are certain by early Sunday and some large and potentially destructive slides possible. Backcountry travel in avalanche terrain should be avoided Sunday. WASHINGTON CASCADES EAST OF THE CREST... AVALANCHE WATCH FOR SUNDAY.... Considerable avalanche danger above 4 to 5000 feet and moderate below Saturday. Increasing danger expected late Saturday night and Sunday becoming high below 7000 feet. Decreasing danger late Sunday becoming moderate below 7000 feet. SNOWPACK ANALYSIS... A series of strong frontal systems have moved across the area over the past three days with fluctuating freezing levels and periods of very strong winds. Total storm snow accumulations have been between 20 to 30 inches over most west slope areas and 5 to 10 inches over the east slopes. A period of mild and sunny weather preceded the recent snow. This produced a crust on most slopes that is now buried under the recent snow. Recent field reports, avalanche control results and natural avalanches all have indicated a weak bond of recent snow to this crust exists in many areas, mainly above 5000 feet. Several avalanche cycles have also accompanied the recent storms and helped to lower the present danger. Daytime warming Friday along with precipitation produced a widespread natural avalanche cycle in the Snoqualmie Pass area. One skier was caught but fortunately not buried by about a 14 inch naturally released slab on a well known ski run. Recent very strong winds and some 6 to 10 inches of new snow has accumulated since early Friday. The strong westerly winds were recorded with sustained winds of 30 to 40 mph with gusts from 50 to over 100 mph late Friday and Friday night. This has scoured much of the recent snow on exposed slopes while depositing dense wind slabs on a variety of exposures. The dense new wind slabs overly earlier snow deposited over the past few days. This is making triggered slab releases probable on steep slopes that have been loaded by wind transported snow, mainly northeast through southeast facing above about 4000 feet where the strongest winds occurred. At lower elevations, periods of daytime warming have helped to settle recent snow or develop new near surface crust layers, leading to an overall lower danger. SATURDAY... Decreasing light snow showers early Saturday may continue to add additional loading to lee slopes, mainly easterly facing slopes with unstable slabs remaining probable on lee slopes above about 4000 feet. Decreasing showers and winds later Saturday through early Saturday night should lead to a further slowly decreasing danger. Increasing rain or snow and significant warming with increasing winds should lead to a rapidly increasing danger late Saturday night. SUNDAY... Moderate to heavy rain or snow and further and significantly rising freezing levels early Sunday should cause an increasing danger. The danger is expected to become high to extreme above about 5000 feet early Sunday with natural avalanches certain and large and potentially destructive slides possible, especially on slopes that have received the greatest amounts of recent snow and that have yet to slide over the past few days. Travel in avalanche terrain should be avoided Sunday. Decreasing precipitation and winds late Sunday and the likelihood of prior natural avalanches should lead to a decreasing danger late Sunday. **********************************************************