Unstable storm slabs on Andesite Peak.

We toured on Andesite Peak today assessing storm slabs and wind slabs. We started out from Donner Pass in all snow conditions with about 8-10 inches of high density new snow from last night in this area. Snowfall rates varied in intensity, but additional accumulation during our tour was minimal.

Breaking trail, we began to trigger storm slab cracking above 7,400'. We identified a 6 inch storm slab that was 4F+ hard over 4F hard. ECT scored ECTP-5 on this layer and we were able to trigger storm slab avalanches on test slopes that were steeper than 35 degrees.

Moving up towards treeline and into wind exposed terrain, snow surface cracking stopped occurring. Near treeline and above treeline wind slabs were very dense and well bonded. We were unable to trigger any cracks or slab failures on our usually productive wind slab test slopes in above treeline terrain. Interesting day in that storm slabs without a PWL were more reactive than wind slabs in this area.