Avalanche investigation of a slide that buried a skier earlier in week
Signs of Unstable Snow
A group of skiers triggered an avalanche on a steep SE face on 2/21(see earlier observation from that date). PAC forecasters went to the area to gather information to accompany an official report. The terrain was heavily wind-loaded and the tracks from the reporting party were barely visible. Layer of concern was the slick sun crust, facet combination at 70cm.
Observed Avalanche Problem #1:
Soft storm slab 15-30 cm thick with multiple weak layers present in upper snowpack, buried weak layer that was triggered by reporting party at 70 cm was a crust/facet combo buried formed 2/10-2/11. This layer has been relatively active since it was buried. PAC received several other reports of human-triggered avalanches on this layer on both 2/20 and 2/21. The avalanche hazard was rated at moderate on the day of the incident