Persistent Slabs
- Alta montaña
- Límite del bosque
- Bajo el límite del bosque
- Probabilidad
- Possible
- Tamaño
- 2–3
A persistent weak layer of faceted snow formed in late November. 2 to 4 feet of snow from early December has settled over the weak layer to form a cohesive slab. Persistent slab avalanches release in surprising ways. They can propagate across and beyond terrain features that would otherwise confine surface instabilities such as wind or storm slabs. In some cases, persistent slab avalanches can be remotely triggered from adjacent slopes. You are most likely to trigger a persistent slab avalanche from areas of thinner snow where the weak layer is less than 3 feet below the snow surface. These weaknesses are most likely to be found on northerly aspects, near and above treeline, in steep, rocky terrain.