Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Unlikely
- Size
- 1.5–2.5
It is unlikely that you will trigger a large avalanche that fails on weak snow on the ground. Basal facets are buried 2-4 feet in the Snake River Range and have not had any observed avalanche activity in 3 weeks. Very steep, wind-scoured, rocky terrain is the most likely place to find a trigger point. Wind-affected areas and rocky outcrops often hide thin spots in the snowpack where you can impact the buried weak layer. Signs of instability, such as cracking or collapsing, may not be present before triggering a persistent slab avalanche. Evaluate terrain for locations where the snowpack is thin. Sheltered terrain that is not affected by the sun and wind will hold the best and safest riding.
(1/30/2025)
This persistent slab avalanche, likely from within the past week, was triggered on a steep, rocky, wind-scoured NW slope at 10,400' in the Gros Ventre Range.
Photo: Bridger-Teton Avalanche Center