Small Wind Slabs and Loose Snow Sluffs on Silver Peak

We found 3 to 4 inches of new snow had fallen in the Silver Peak area since yesterday. On the way up we dug several hand pits to look at the interface between the new snow and the old near surface facets and to look for any remaining buried surface hoar. In one meadow around 7000 ft, we did find some old broken down surface hoar buried in the snowpack but could not get any unstable test results when testing it. We did not find that layer in any of the other locations we dug. Below 7000 ft, our pits showed that the precipitation started as rain during the night because there was a thin rain crust at the base of the new snow. Above 7000 ft, this crust disappeared. All of our data and observations indicated that the new snow and the old near surface facets had not bonded well to each other. However, in below treeline terrain and in sheltered near treeline terrain, the new snow was not cohesive enough to form a slab and there was not actually that much new snow. When we ski cut some small test slopes, we found that the new snow would slide off the old near surface facets as a shallow loose dry sluff. 

Once we moved into more exposed near and above treeline terrain, we did find some wind slabs. They were small and did not extend very far downslope on the test slopes we looked at. The largest one we found was on the edge of a larger wind-loaded slope. It was about 1 ft deep but got rapidly thinner down the slope. It thinned to a few inches thick within 10 to 20 ft from the ridge. We still avoided larger slopes with more obvious wind-loading in favor of the non-wind-affected sheltered slopes.

Photo 1: Small ski kick triggered wind slab on the edge of a wind loaded slope in near treeline terrain.

Photo 2: Ski cuts triggered loose dry sluffs with the new snow sliding on the old near surface facets.