Observations from Little Truckee Summit

Today was the third day of a Sierra Avalanche Center motorized level 1, the group spent the day travelling though a variety of terrain in the Little Truckee Summit area. We had cool temps in the morning, which quickly rose well above freezing by mid day. Today felt like the warmest day in a while. Winds were calm in the lower valleys and meadows, but as we gained elevation winds became much more noticable with NE Gusts of 15-20mph along ridgelines. We noted some blowing snow in the Grills area, but with not much snow available for transport we did not see evidence of anything resembling a slab on the lee ward side of the slope. As expected, snow surfaces were extremely variable across the areas we travelled, these surfaces ranged from firm, frozen snow in the morning that softened by noon, to areas of surface faceted snow in lower elevation protected terrain. The long term affects of the sun are very present, what were once smooth slopes are now extremely textured and uneven due to day time warming and no longer harbor the same "corn like" characteristics they did a few weeks ago. In sheltered terrain near surface faceted snow is alive and well, we have been returning to areas that share similarities in the terrain to see how these weak grains have been changing. The biggest noticable change has been the breakdown of the crusts in the upper snowpack and faceted grains becoming more wide spread below treeline in sheltered areas. We have been finding this weak, faceted snow on NW-N-NE aspects near and below treeline. Our class targeted this terrain to do compression tests on throughout the weekend with the intent of identifying potential weak layers in the upper snowpack . Our tests had consistent sudden failures 10-15cm below the surface, all failing on the same layer.