Persistent Slabs
- Alta quota
- Limite del bosco
- Sotto il limite del bosco
- Probabilità
- Unlikely
- Dimensione
- 1–2
While unlikely, you have the highest odds of triggering a persistent slab avalanche on previously wind-loaded slopes above about 9,200 feet that face the northern half of the compass. These areas harbor weak layers (sugary facets, surface hoar, and crust + facet combinations) that remained dry during the March heat waves.
Steep, rocky, wind-affected slopes with variable snowpack depths are most suspect. Smooth snow pillows and dunes indicate the wind has been at work. You probably won't experience obvious signs of instability, such as snowpack cracking and collapsing, before triggering a slide.
Additional Discussion - Wind Slabs: In the White Cloud Mtns, forecasted snowfall and wind could form isolated, thin wind slabs in exposed terrain this afternoon and evening. You are most likely to find fresh slabs on exposed slopes that faces the eastern half of the compass, after at least 2-3" of new snow falls. Keep your eyes peeled if you're traveling in this area late this afternoon or evening.
(3/17/2026) A pair of large natural slab avalanches that failed on weak sugary facets buried 2 feet below the surface. N aspect @ 8300'. These probably occurred over the March 14/15 weekend.
Photo: Sawtooth Avalanche Center