Deep Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 2–3
The potential for humans to trigger deep slab avalanches with depths to five feet continues. If triggered these dangerous slabs will fail on a deeply buried layer of faceted snow that persist on all aspects above 7500 feet. These slabs could be triggered by a single person hitting a shallow weak spot or more easily by larger triggers such as snowmachines or groups of skiers. Previous tracks are not an indication of stability. Deep persistent slab avalanches are the most difficult avalanche problem to assess, predict and manage. They can remain unstable for weeks or months.