####018003798#### WWUS86 KPQR 292000 SABOR Summary Avalanche Forecast for Mt Hood area Northwest Weather and Avalanche Center Seattle Washington 1159 AM PST Wed Feb 29 2012 This forecast applies to back country avalanche terrain below 7000 feet and does not apply to developed ski areas or highways. Avalanche Forecast Mt Hood Area- Wednesday and Wednesday night: High avalanche danger on lee slopes above 6000 feet and considerable elsewhere slowly increasing Wednesday and becoming high on lee slopes above 5000 feet and considerable below. Danger slightly decreasing late Wednesday. Thursday and Thursday night: High avalanche danger on lee slopes above 6000 feet and considerable elsewhere early Thursday. Little change in the danger expected Thursday except for slight increase on sun exposed terrain. Danger slowly decreasing Thursday night and becoming considerable above 5000 feet and moderate below. Snowpack Synopsis A series of storms brought heavy snow and strong winds last Friday and Saturday and significant avalanche activity last weekend. Since then, decreasing light showers and some clearing brought a brief and slow decrease in the danger Monday through early to mid Tuesday. However, increasing snowfall and winds at low freezing levels late Tuesday into Wednesday morning in the Mt Hood area have once again produced an increasing avalanche danger. This weather has accentuated the danger on lee slopes beneath higher ridges receiving stronger winds where human triggered slide are likely to very likely. Due to shifting winds, current lee slopes include a variety of exposures depending on location and elevation, but are most likely north through east exposures. Wednesday and Wednesday night Moderate to occasionally heavy snowfall and moderate to locally strong and shifting winds are expected for most of Wednesday at low freezing levels. This should result in increasingly dangerous avalanche conditions especially on wind loaded terrain. Resulting wind slabs or cornices should be very suceptible to human triggers on many lee slopes Wednesday, along with some natural slide activity as well. As a result, back country travel in steeper wind loaded avalanche terrain is not recommended Wednesday. Gradually decreasing showers and winds are expected overnight into early Thursday and this should allow for a slight decrease in the danger. Thursday and Thursday night Light to moderate showers are expected Thursday morning, slightly increasing in the afternoon. However, along with significantly decreased winds and continued cold temperatures, generally small new snow accumulations should not significantly add to the danger. However, the cold temperatures should continue to slow stabilization of existing slabs while some sun breaks should produce a slight danger increase on sun exposed terrain. Also, recent wind deposits of 1-2 feet or more should remain suceptible to human triggering...especially on steeper lee terrain not experiencing recent slide activity. Generally light winds and some clearing should combine with continued low temperatures to produce a slight decrease in the danger Thursday night. n/a n/a 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 www.nwac.us. Moore/Northwest Weather and Avalanche Center Seattle Washington References 1. http://www.nwac.us/####018004679#### WWUS86 KSEW 292000 SABWA Summary Avalanche Forecast for Olympics and Washington Cascades Northwest Weather and Avalanche Center Seattle Washington 1200 PM PST Wed Feb 29 2012 This forecast applies to back country avalanche terrain below 7000 feet and does not apply to developed ski areas or highways. Avalanche Forecast Olympics- Washington Cascades near and west of the crest- Wednesday and Wednesday night: High avalanche danger on lee slopes above 5000 feet and considerable elsewhere slowly increasing Wednesday...especially in the south...and becoming high above 5000 feet and considerable below. Danger slightly decreasing Wednesday night. Thursday and Thursday night: High avalanche danger on lee slopes above 6000 feet and considerable elsewhere early Thursday. Little change in the danger expected Thursday except for slight increase on sun exposed terrain. Danger slowly decreasing Thursday night and becoming considerable above 4000 feet and moderate below. Washington Cascades east of the crest- Wednesday and Wednesday night: Considerable avalanche danger below 7000 feet slightly increasing Wednesday and becoming high on lee slopes above 6000 feet and considerable elsewhere. Danger slightly decreasing Wednesday night. Thursday and Thursday night: Considerable avalanche danger below 7000 feet early Thursday. Little change in the danger Thursday except for slight increase on sun exposed terrain. Danger slowly decreasing Thursday night and becoming considerable above 5000 feet and moderate below. Snowpack Synopsis A series of storms brought heavy snow and strong winds last Friday and Saturday and significant avalanche activity last weekend that involved some older buried weak layers...and produced several incidents along with some partial burials. Since then, decreasing light showers and some brief clearing brought a brief and slow decrease in the danger Monday through early to mid Tuesday as the recent heavy storm snow settled. However, increasing snowfall and winds at low freezing levels Tuesday afternoon and night in the Olympics and late Tuesday through early Wednesday in the Cascades have once again produced an increasing danger. This weather has accentuated the danger on lee slopes beneath higher ridges receiving stronger winds where human triggered slide are likely to very likely. Due to shifting winds, current lee slopes include a variety of exposures depending on location and elevation, but mainly include northwest, north and northeast through east exposures. Wednesday and Wednesday night Increasing light to moderate snow showers are likely in the north and central Cascades Wednesday with moderate to occasionally heavy showers in the south. Along with some locally strong and shifting winds at low freezing levels, this should produce increasingly dangerous avalanche conditions. Unstable slabs or cornices should be very suceptible to human triggers on most wind loaded avalanche terrain on Wednesday, along with some natural slide activity as well. As a result, back country travel in steep lee avalanche terrain is not recommended Wednesday. Gradually decreasing showers and winds are expected overnight and this should allow for a slight decrease in the danger. Thursday and Thursday night Light to occasionally moderate showers are expected Thursday morning, slightly increasing in the afternoon, along with significantly decreased winds and continued cold temperatures. Although generally small new snow accumulations are likely, the cold temperatures should continue to slow stabilization and maintain the threat of further human triggered wind slabs on steeper lee terrain. Meanwhile some sun breaks should produce a slight danger increase on sun exposed terrain. While some increase in winds is expected near higher ridgetops overnight, generally light winds and some clearing in most locations should combine with continued low temperatures to produce a slight decrease in the danger. n/a n/a 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 www.nwac.us. Moore/Northwest Weather and Avalanche Center Seattle Washington References 1. http://www.nwac.us/