Wind Slabs and Shooting Cracks on Tamarack Peak

4 to 6 inches of new snow had fallen by early afternoon in the Tamarack Peak area today. In sheltered areas, cracking around our skis while skinning, hand pits, and formal snowpit work indicated that the new snow was not bonding well to the old snow surfaces. In sheltered areas, new snow accumulation had not yet reached a point where storm slabs had become widespread, but observations did indicate that if enough new snow accumulates storm slabs could pose a problem today. In these areas, soft new snow rested on a more dense layer of new snow that all rested on top of the old loose weak snow (near surface facets).

In more exposed areas continuous and significant wind loading was occurring all day.  By 1 pm wind slabs up to 16 inches deep had formed in wind loaded areas. Ski cuts on wind loaded test slopes triggered small wind slab avalanches and shooting cracks up to 20 ft. in length. These wind slabs also failed on the old snow surface. 

Photo 1: Wind slab failure triggered by a skiers weight on a NE facing test slope at 9360 ft. 

Photo 2: Cracking on a wind loaded test slope.

Video: Wind slab failure on the same test slope as shown in photo 1.