Wind Slabs, Cracking in the Storm Snow, and Buried Surface Hoar on Andesite

We could see blowing snow and large cornices on slopes next to I80 driving up to Donner Summit. Once we got out of the truck and started skinning, we found about 1 foot of new snow accumulation in sheltered areas. This fresh snow had a graupel layer near its base and a density change about 6 inches below the surface. As we moved through the snow, it cracked around our skis at the density change on all aspects. It also broke deeper on the more north-facing slopes. We found the buried surface hoar layer when we dug into the snowpack to see what was responsible for this deeper failure. We avoided large steep slopes, but we did find a few small, inconsequential test slopes to jump on. Ski kicks triggered some small soft storm slabs on these test slopes. 

We continued up the ridge into more wind-exposed terrain. Here, we saw widespread signs of wind-loading during this storm, including blowing snow, new cornices above slopes, snow drifts, and ripples on the snow surface. Again we avoided going near any large slopes and targeted small test slopes for data collection. When we stepped on the test slopes or dropped small pieces of cornices onto them, we triggered wind slab avalanches up to 18 inches deep. We saw another small avalanche near the summit of Andesite that a previous skier had triggered. This avalanche only moved a few feet from the summit and did not run down the open face of the peak. 

Snowfall continued throughout our entire tour. The snowfall intensity waxed and waned between less than an inch an hour to up to 2 inches per hour.