Persistent Slabs
- Alta montaña
- Límite del bosque
- Bajo el límite del bosque
- Probabilidad
- Unlikely
- Tamaño
- 1.5–2
Slab avalanches breaking into old weak layers several feet deep have become unlikely, but not impossible. Higher elevation, northerly facing terrain still holds a dry, winterlike snowpack; thus we can't completely eliminate the potential for a rare but large slab avalanche on these aspects. The most suspect terrain is where snow coverage is shallower, especially on convex, unsupported slopes or near rock bands. You are most likely to trigger a slide from a shallower spot on the slope. If you are skiing or riding in that type of terrain, reduce your group's exposure during uphill travel and choose appropriate safe zones from a large avalanche while descending. Let your friend wrestle their stuck snowmobile off of suspect slopes by themselves.
Example of our most recent persistent slab avalanche that likely failed around March 30th. This large avalanche highlights the type of terrain that remains most worrisome: northerly, rocky, and unsupported.