Persistent Slabs
- Alta quota
- Limite del bosco
- Sotto il limite del bosco
- Probabilità
- Possible
- Dimensione
- 2–2.5
Slabs that formed in early February rest above a variety of ugly, widespread, weak layers (facets, surface hoar, crusts, and combinations). Yesterday, a large persistent slab avalanche was triggered on a NW facing slope on Patterson Pk above Hailey. Observers and professionals around the Wood River Valley continue to report frequent collapsing or whumpfing. These are clear signs that triggering one of these slides remains a real possibility. Persistent Slabs can release in surprising ways and break much wider than expected. You are most likely to trigger a dense, 2-4 foot thick avalanche where:
- The slab is less than about 2' thick—this is the case on many slopes surrounding the Wood River Valley. Relatively shallower spots may exist where the wind frequently blows.
- Any part of the slope you are on or connected to is steeper than about 35 degrees
- The slope faces the northern 2/3 of the compass
- A smaller wind slab or loose snow avalanche overloads the buried weak layers
(2/18/2025) A skier on Patterson Pk near Hailey triggered this large avalanche. After several turns on the slope, the slide broke above and around them. Thankfully, the skier was able to ski ahead and to the side of the slab. NW @ 8,050'.
Photo: Sawtooth Avalanche Center