Quick report
- Red Flags
- Wind Loading, Poor Snowpack Structure
Travel was across multiple drainages in search of the PWL that has been making all the headlines. I found this issue in multiple locations, however it was the wind that caught my attention today, particululary as it loaded aspects harboring this menace.
Photos:
1. Birthay chutes wind loading.
2. Twins wind loading.
3. ECT result on SW facing Columbine Bowl.
4. Slab character over weak layer.
Snowpack
- Instability Comment
- <p>Moderate to Strong SW winds blowing across the Twins Massif all afternoon. Upper Birthday chutes were actively loading and beginning to look rounded and fat. Winds were also sweeping through the drainages of Red Pine and Maybird. The apline terrain was channeling the current of wind and it seemed as though winds were out of the SE where I performed a snow profile and tests. All the storm snow from yesterday is being whipped up into hard slabs above 10,000'. </p> <p>Compounded by the wind loading, there is a persistent weak layer of small grain (1mm or less) faceted crystals on the southerly facing slopes. These have been reportedly associated with a crust, but the location where I dug, it was nearly imperceptible. However, the facets were reactive- Full propagation ,ECTP14. and very easy results in shovel shear tests. The layer is located 45cm down and the slab is pencil -1F hard. This appears to be the slab/weak layer combination that is necessary to activate these weaknesses. No avalanches were observed on this layer today. </p>