830 AM PST SAT MAR 01 2008 && ZONE AVALANCHE FORECASTS * OLYMPICS, WASHINGTON CASCADES NEAR AND WEST OF THE CREST, MT HOOD AREA- Saturday: CONSIDERABLE avalanche danger above 5000 feet and MODERATE below increasing and becoming CONSIDERABLE below 7000 feet late Saturday, except locally HIGH on northeast through southeast facing slopes above 5 to 6000 feet Saturday night: danger gradually decreasing late Saturday night and early Sunday Sunday: slightly increasing danger on sun exposed terrain, otherwise slowly decreasing danger on shaded terrain Sunday night: slowly decreasing danger overnight, but slightly increasing early Monday mainly Olympics and northern Washington Cascades * EAST SLOPES WASHINGTON CASCADES- Saturday: CONSIDERABLE avalanche danger above 6000 feet and MODERATE below increasing and becoming CONSIDERABLE above 4 to 5000 feet late Saturday with greatest danger on southeast through northeast facing slopes near the crest Saturday night: danger gradually decreasing late Saturday night and early Sunday Sunday: slightly increasing danger on sun exposed terrain, otherwise slowly decreasing danger on shaded terrain Sunday night: slowly decreasing danger SNOWPACK ANALYSIS In most areas of the Olympics and Cascades near and west of the crest, increasing moderate rain or snow changed to mostly snow overnight with accumulations generally ranging from 4 to about 12 inches. With rain changing to snow below about 4 to 5000 feet, a relatively good bond of new snow is expected to the old moist or crusted snow surface and this has helped to limit the danger increase to moderate. However, field reports early Saturday indicate that some weak new layers have developed within the new snow due to variations in snowfall rates and wind speeds overnight and these may result in some shallow slab activity as further loading occurs. At higher elevations above about 5000 feet, cooling temperatures prior to the onset of precipitation produced a weaker bond of new snow to the relatively firm but highly variable old snow surface. Along with moderate to strong winds and some weak layers within the newly deposited snow, this weather resulted in a generally increased and considerable danger above about 5000 feet, especially on north, northeast and east facing slopes where shallow but increasing winds slabs of 6-12 inches are probable, mostly releasing on the old crust or firm old snow surface. Smaller new snow accumulations along the Cascade east slopes have produced a less significant increase in the danger. However, a similar snow structure exists and a considerable danger exists on lee slopes above about 6000 feet with a moderate danger below, especially on higher wind loaded terrain near the crest. Fortunately in most locations, the old more deeply faceted layers produced during cold weather in December and January have been bridged by several strong crusts or harder wind slab layers and should not contribute to current avalanche danger. However, in some higher wind exposed locations, the magnitude of earlier faceting is rather evident and such weakening may become more of a concern during future spring warming or sustained heavy rain events. DETAILED FORECASTS SATURDAY, SATURDAY NIGHT Generally moderate snow showers should increase mid-late Saturday morning and afternoon, with a Puget Sound convergence expected to enhance snowfall near Stevens Pass later Saturday morning and early afternoon and near Snoqualmie Pass later Saturday afternoon and evening before diminishing later Saturday night and early Sunday. Along with moderate winds and low freezing levels, this weather should continue to gradually increase the existing avalanche danger, especially on northeast through southeast exposures where locally HIGH danger is expected above about 5 to 6000 feet. Increasingly cohesive wind transported snow mid-day and Saturday afternoon should be deposited over some lower density layers developed during lighter showers early Saturday, with some human triggered 12-18 inch soft slabs becoming probable to likely later Saturday. Although recently very nice weather has brought thoughts of spring and stable snowpacks to many, back country travelers are urged to leave such thoughts behind when venturing into avalanche terrain this weekend. Please realize that winter isnt over til its over and use increasing caution in avalanche terrain on Saturday with stability tests strongly encouraged. Gradually decreasing winds and showers later Saturday night and early Sunday should allow for a slow decrease in the danger. SUNDAY, SUNDAY NIGHT Further decreasing clouds with scattered light showers ending early Sunday should be followed by partly to mostly sunny skies Sunday morning, and considerable filtered sunshine through increasing high clouds Sunday afternoon. Along with generally decreased and relatively light winds and slight warming, mainly in the south, this weather should allow for a slowly decreasing danger on most lee slopes as recent wind slabs begin to settle. However, a locally increased danger is probable on sun exposed terrain as strengthening early March sun weakens and melts snow from tree boughs and rock faces, thus increasing the potential for both natural and human triggered, loose and isolated slab slides on the slopes below. Clouds should increase Sunday night, with light rain or snow showers developing in the Olympics and north-central Cascades early Monday. Along with increasingly strong ridgetop winds, this should lead to slightly increasing danger in the north and Olympics. In most other areas, variable high clouds, lighter winds and some warming should allow for a slight decrease in the danger as recent wind slabs settle and previously sun warmed surface snow refreezes. &&