8 AM PST THU FEB 14 2008 && ZONE AVALANCHE FORECASTS * OLYMPICS, WASHINGTON CASCADES NORTH OF STEVENS PASS- Moderate avalanche danger below 7000 feet slightly increasing on Thursday, mainly on sun exposed terrain. Danger slightly decreasing Thursday night. Danger slowly increasing later Friday morning and afternoon, becoming considerable above 5 to 6000 feet and moderate below. Slightly decreasing danger Friday night. * WASHINGTON CASCADES FROM STEVENS PASS SOUTHWARD TO MT RAINIER- Moderate avalanche danger below 7000 feet slightly increasing on Thursday, mainly on sun exposed terrain. Danger slightly decreasing Thursday night. Slightly increasing danger expected mid-day and Friday afternoon, but danger decreasing slightly Friday night. * WASHINGTON CASCADES FROM MT RAINIER SOUTHWARD, MT HOOD AREA- Moderate avalanche danger below 7000 feet slightly increasing on Thursday, mainly on sun exposed terrain. Danger slightly decreasing Thursday night with little change in the danger expected on Friday. Slightly decreasing danger Friday night. SNOWPACK ANALYSIS Light to moderate amounts of new snow were received in most areas mid-late Tuesday through early Wednesday. This snow fell at gradually lowering temperatures and formed a good bond with the old wet or slowly refreezing snow surface that was present prior to snowfall in most locations. While this bond helped to limit the danger increase, moderate southwest to northwest winds produced some shallow slabs over the strengthening though still relatively thin near surface crust on lee slopes. Field reports on Wednesday indicated some shallow, 6-8 inch skier triggered soft slabs being released on east and northeast exposures above about 5000 feet. As a result, although a moderate danger exists in most areas, the danger is slightly accentuated on southeast through northeast exposures where pockets of considerable danger may exist on steeper terrain, mainly above about 5 to 6000 feet. While some partial clearing mid-late Wednesday may have allowed for a weak sun crust to develop on sun exposed terrain, this should not be a significant factor in stability considerations. Some surface hoar and near surface faceting near or below the recent crust have also been reported in some locations early Thursday. However, neither of these weak layers are expected to be significant factors in future stability concerns as either light rain on Friday or future warm and mostly fair weather over the weekend should destroy or severely limit their effectiveness as future weak layers. DETAILED FORECASTS THURSDAY, THURSDAY NIGHT Increasing mid and high clouds are expected across north- central Washington on Thursday along with a chance of some scattered light showers in the extreme north. Otherwise variable high clouds and considerable sunshine or filtered sunshine are expected in south-central Washington and northern Oregon. Along with slowly rising freezing levels, generally light winds in most locations and some sunshine or filtered sunshine, this weather should produce a slight increase in the danger Thursday, especially on directly sun exposed southeast through southwest exposures. The greatest danger increase should be on steeper terrain beneath trees or cliffs where snow melting and releasing from tree boughs or rock faces may trigger mostly small loose or isolated soft or wet slab releases within the new snow over the slowly strengthening near surface crust. At this time, most releases should primarily involve only the most recently deposited new or recently wind transported snow. Also some wind transport by northerly winds at higher elevations may create additional shallow slabs on south and southeast exposures above about 6000 feet. Increasing mid and high clouds are expected in the north Thursday night, with variable high clouds continuing in the south. This should allow for a slight decrease in the danger overnight as further snowpack settlement proceeds and wet surface snow refreezes and forms a thin melt freeze surface crust on previously sun exposed terrain. FRIDAY, FRIDAY NIGHT Increasing clouds and light rain or snow are expected to spread across the Olympics and north-central Washington Cascades Friday, with increasing clouds and some light showers reaching the southern Washington Cascades and Mt Hood area Friday afternoon and evening. Along with gradually lowering freezing levels and some increase in winds mainly in the north, this should produce a slow and relatively limited increase in the danger north of Stevens Pass as higher density snow or rain loads existing shallow slabs. Further to the south, this weather should maintain or only slightly increase generally moderate danger as very minor precipitation amounts should slightly load or weaken existing shallow slabs. Decreasing showers and winds along with further brief cooling Friday night should allow shallow slabs to settle and wet surface snow to refreeze, thus producing a slight decrease in the danger. &&