0745 AM PST WED JAN 23 2008 && ZONE AVALANCHE FORECASTS * OLYMPICS, WASHINGTON CASCADES, MT HOOD AREA- Locally CONSIDERABLE danger on west and southwest exposures above 6000 feet early Wednesday slightly decreasing later Wednesday and Thursday; otherwise MODERATE avalanche danger below 7000 feet through Thursday. SNOWPACK ANALYSIS Increasing snowpack settlement during the past few days continues to allow for slow stabilization of the upper part of the snowpack and a very slow reduction of the avalanche danger in most areas. However, very cold temperatures have made this stabilization a very slow process and are continuing to facet the snow near last Mondays crust, as well as helping to produce generally weakening and faceted snow throughout much of the top 1-3 feet of near surface snow. Also, strong east to northeast winds mid-late Sunday and Monday created some unstable wind slabs and accentuated the danger on west and southwest exposures, where human triggered slides or isolated hard slabs remain probable above about 6000 feet and possible below. With intermittent clearing also producing sporadic surface hoar mid-late last week, some buried surface hoar may also exist under these recent wind slabs and this may result in some sensitive though relatively local instabilities. Overall then, recent weather has produced some highly variable snow conditions dependent primarily on exposure: on wind exposed terrain, the recent high winds may have scoured many windward slopes down to a relatively stable old crust or wind hardened surface. On adjacent steeper lee terrain near higher ridges, winds may have produced some sensitive wind slabs ranging from 6 inches to 2 feet or more, with these slabs developing over potential weak layers of buried surface hoar or some lower density snow over the crust formed in mid-January. Some smaller though perhaps still sensitive wind slabs may also exist on wind affected west exposures at lower elevations near the Cascade passes. However, in wind sheltered areas, some relatively stable powder or recycled powder has been reported, though some cross loading by recent winds may have produced local shallow slabs on steeper terrain to the lee of minor ridges. All in all, the past, current and expected weather have made and should make for a snowpack structure that will be highly susceptible to a significant danger increase whenever more normal wintertime snowfall returns to the region. Most current model forecasts indicate that while a relatively weak disturbance passing mostly west of the region on Thursday should have little affect on the current danger, a more significant danger increase is likely next weekend when moderate snowfall and increasing winds should load a very weak snowpack structure. DETAILED FORECASTS WEDNESDAY, WEDNESDAY NIGHT Mostly fair and cold weather early Wednesday should be followed by continued mostly fair and slightly warmer weather Wednesday, with most warming confined to mid and upper elevations in the southern Washington Cascades, Mt Hood area and the Olympics. Along with continued relatively light ridge top winds, this should allow for a slow and slight decrease in the danger as recent winds slabs continue to slowly settle. However, cold temperatures in most sun shaded and lower elevation terrain Wednesday should make any stabilization a very slow process, and cold, east winds near the Cascade passes should help maintain some shallow slabs on west exposures. As a result, back country travelers should use considerable caution when approaching slopes showing evidence of wind transport, with stability and slope tests strongly recommended to determine both the bond of recent snow to last weeks crust as well the presence of any buried surface hoar. Although some high clouds are expected overnight, this weather should provide excellent conditions for continued surface hoar growth in wind sheltered areas, and relatively cool temperatures in most locations should allow for continued faceting and weakening of snow layers near last Mondays crust. All of these potential weak layers should be monitored in the days ahead as they may become important factors in promoting avalanche danger when future snow loading is received. THURSDAY, THURSDAY NIGHT Variable high clouds Wednesday night should be followed by variable mid and high clouds spreading southward on Thursday. However, little or no snowfall is expected except for a chance of flurries in the Olympics Thursday morning, and some very light snow or light snow showers in the southern Washington Cascades and Mt Hood area Thursday afternoon and evening. Along with decreasing pass winds Thursday afternoon and continued relatively light ridgetop winds and low freezing levels, this weather should have little affect on the current danger. However, the relatively cold weather should help to maintain some unstable slabs through a weak and weakening bond to last weeks crust, especially on west and southwest exposures. A slow clearing trend with light winds and low freezing levels Thursday night should have little affect on the current danger, but should once again allow for further faceting and weakening within the upper part of the snowpack as well as further and more widespread surface hoar formation. &&