Our PWL problem is alive and well on all aspects. It is especially sensitive on the Northerlies. Yesterday we experienced widespread collapsing while traveling on N, NW, and SW aspects. I continued to experience widespread collapsing today while traveling primarily on Northerlies. Other touring parties reported widespread collapsing as well. I also got propagation in two ECT's on NE facing slopes, one BTL, one NTL.
The weak layer is easily seen in this photo
Smaller facets (1mm) were observed at the top of the weak layer where the failure occured.
Larger facets (2mm) were observed near the ground.
A few things stand out to me about these pits. They are both in sheltered areas and have not been previously wind loaded this season. Both snowpacks are shallow with HS under 70cm. They are simple, with not many layers, and the weak, faceted layer is extremely obvious in both pits. Extended column tests produced propagation in both pits, with a low score (ECTP 7) in the Coyote Glades. These results combined with continued widespread collapsing tell us the snowpack is sensitive right now and human triggered avalanches remain likely in steep terrain.
The remotely triggered avalanche in Horse Creek is a huge red flag and an indication that Northerly aspects are sensitive to the weight of a skier or rider right now. This slope was heavily wind loaded (max depth 6.5 feet). This is a great example of the wind-drifted slopes in the alpine that are hanging in the balance just waiting for a trigger. These thick, hard slabs of wind-drifted snow are sitting on top of a very weak snowpack as illustrated by the Horse Creek avalanche. There are many more slopes in the alpine that have this dangerous structure.
