Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 3
Slabs of wind drifted snow formed earlier in the week have largely stabilized, but in some cases they are resting on top of faceted weak layers that were buried near the surface as the human triggered avalanche detailed above demonstrates. I don't think this problem is widespread, but the only way to make sure it's not there is to dig down a foot or two and make sure before you commit to a slope.
A lower likelihood, but much higher consequence scenario remains for avalanches failing down to the persistent weak layer (PWL) at the base of the snowpack. Deep wind-drifts have added more stress to this buried weak layer, particularly on northerly aspects right around treeline and above. I have not observed any natural activity as a result of this load, but it may have increased the likelihood for a human trigger. Again, this is a hard call to make. If you chose to venture into this terrain, minimize your risk by avoiding steep, rocky, thinner snowpack areas and slopes with complex terrain features.