Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 2
Recent winds and warm temperatures helped to form a strong cohesive slab and it's resting on fragile, old October snow... or what we call a persistent weak layer (PWL). And while last night's storm snow may feel light, fluffy, and harmless we've gotta remember- not only the snow we're riding in, but also the snow we're riding on. Yep... this is the classic "strong snow on weak snow" setup and that's always a dangerous combination in our mountains. This combo makes snow feel strong under our skis, board, or sled and often allows us to get well out onto the slope before the weak layer fails (often around a bush or rock we can't see under the snow), the avalanche breaks above us, and now the entire seasons snowpack crashes down on top of us.
Now here's where it gets tricky... there's a fresh blanket of snow coating our mountains and everything's gonna look white. In fact, it'll be more difficult to determine what slopes held early season snow. But remember... terrain that faces the south half of the compass and lower elevation slopes were bare prior to last weeks big storm. And while there's plenty of gear wrecking rocks and stumps to slam into, there's no old snow and avalanche issues are straight-forward.
