Persistent Slabs
- Hochgebirge
- Waldgrenze
- Unterhalb der Waldgrenze
- Wahrscheinlichkeit
- Unlikely
- Größe
- 1–2
The various persistent weak layers we have been tracking so far this season, faceted rain crusts and surface hoar, are now buried 2 to 3+ feet deep in the snowpack. Regardless of weak layer flavor, they have been trending less reactive recently and appear very stubborn to fail. The generally mild weather followed by cold nights over the last week has promoted significant settlement in the upper snowpack, and the slab is now much stiffer. This makes it more difficult for a rider or machine to penetrate deep enough into the snowpack to impact buried weak layers. Throw in a snowpack capping surface crust and this adds more reinforcement to the stubborn slab.
While we cannot rule out every slope as “totally” free from all avalanche hazards, you could encounter an isolated area that might behave differently. Continue to use safe travel habits while moving in the mountains, and pay attention to how deep you or your machine sinks into the snow if the surface softens from daytime warming.
A large natural avalanche that was probably triggered by rapidly warming temperatures following an extended period of cold, snowy weather. The slide failed on a northeast aspect around 5,350 feet, and we estimated the crown around 4 feet deep, likely failing on a buried persistent weak layer.
Selkirk Mountains. January 14, 2026.
Photo: Chris Bilbrey