Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 2–3
Our current snowpack is harboring a persistent weak layer above 4,500' that can be found across the area on all aspects. This layer is close to the ground, it consists of crust layers and weak sugary snow that developed in early November. Stability tests are proving this layer has the potential to propagate and create avalanches that could fail 2 to 3 feet deep in the snowpack. Cracking and collapsing on this weak layer was observed this week across all zones of the forecast area. This problem is most likely to fail in steep and open terrain that lacks vegetation to anchor the snowpack (rocky or grassy slopes). Stability tests are also showing that thinner snowpacks will be more sensitive to triggers. Stability tests from our thin snowpack of the Purcells were propagating with light force this week, in the West Cabinets we were getting consistent propagation with moderate force on this layer.