Posted: Fri Jun 11, 2010 4:34 amA little more info here regarding the conditions posted by a fellow SPer in another forum.
"This weather has already resulted in increased avalanche activity at a variety of mid and upper elevations as evidenced by this wet slab near Chinook Pass around the 6 to 7000 ft elevation, and the large 3 to 6 ft slide on Mt Rainier around 12,800 ft that caught 11 climbers and skiers early last Saturday. The Mt Rainier avalanche appears to have initiated in an upper layer and stepped down to a deeper weak layer. Recent snowpack information from NPS rangers at higher elevations on Mt Rainier indicate that in addition to the sheer quantity of new snowfall amounts, a worrisome snowapck structure also exists. Field tests around the 11,000 ft level on Tuesday show significant energy stored within the upper part of the snowpack, as well as several weak layers buried within the late May and early June storm deposits. In most areas, the greatest accumulations of this potentially unstable snow structure exist on southeast through northeast exposures where greatest wind drifting has occured. Such widespread snow instability in June underscores the fact that the weather not the calendar dictates avalanche danger on higher elevations in any mountainous terrain.
The most recent storm system to affect the region has begun to move off to the east as of mid-day Wednesday. However, the associated upper level disturbance should maintain rather cool showery weather into late Thursday with another 6 to 10 inches of snow possible above the 7 to 8000 ft level over the next 36 hours and a few inches down to around 6000 ft. Following the departure of this upper level disturbance early Friday, a slow but very substantial warming and drying trend should move over the NW mid-late Friday through Sunday. With mostly fair skies and decreasing winds expected along with the highest freezing levels since last summer (10-12,000 ft late Friday rising to 13-15,000 ft mid-late Saturday and Sunday), the snowpack should become increasingly unstable and dangerous Friday through Sunday, with a wide variety of avalanche activity probable."
"This weather has already resulted in increased avalanche activity at a variety of mid and upper elevations as evidenced by this wet slab near Chinook Pass around the 6 to 7000 ft elevation, and the large 3 to 6 ft slide on Mt Rainier around 12,800 ft that caught 11 climbers and skiers early last Saturday. The Mt Rainier avalanche appears to have initiated in an upper layer and stepped down to a deeper weak layer. Recent snowpack information from NPS rangers at higher elevations on Mt Rainier indicate that in addition to the sheer quantity of new snowfall amounts, a worrisome snowapck structure also exists. Field tests around the 11,000 ft level on Tuesday show significant energy stored within the upper part of the snowpack, as well as several weak layers buried within the late May and early June storm deposits. In most areas, the greatest accumulations of this potentially unstable snow structure exist on southeast through northeast exposures where greatest wind drifting has occured. Such widespread snow instability in June underscores the fact that the weather not the calendar dictates avalanche danger on higher elevations in any mountainous terrain.
The most recent storm system to affect the region has begun to move off to the east as of mid-day Wednesday. However, the associated upper level disturbance should maintain rather cool showery weather into late Thursday with another 6 to 10 inches of snow possible above the 7 to 8000 ft level over the next 36 hours and a few inches down to around 6000 ft. Following the departure of this upper level disturbance early Friday, a slow but very substantial warming and drying trend should move over the NW mid-late Friday through Sunday. With mostly fair skies and decreasing winds expected along with the highest freezing levels since last summer (10-12,000 ft late Friday rising to 13-15,000 ft mid-late Saturday and Sunday), the snowpack should become increasingly unstable and dangerous Friday through Sunday, with a wide variety of avalanche activity probable."