Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 2–2.5
The distribution of the current persistent slab avalanche problem has narrowed after last week's heat wave. Weak layers in the upper snowpack have become less concerning as they often saw melt water drain through them. Now, the focus has turned back to old facet layers in the bottom half of the snowpack. Don't expect to see any feedback or obvious red flags from this avalanche problem. The problem will remain quiet until it receives a heavy load from a cornice fall, or a light load that finds just the right trigger point where the slab thins above those facets. Persistent slab instabilities are even more isolated below treeline, but you should still stay alert on very steep or unusually shallow slopes.
A large persistent slab on Gothic triggered by a shallower wet avalanche on 3/25.