Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1.5–2.5
The east wind event last week built thick slabs atop weak snow on leeward slopes. The slabs are thick in areas downwind of expansive fetches where lots of old snow was available to be transported across the ground and into avalanche start zones. These old slabs are the primary concern today. You are most likely to find these slabs in areas that you aren’t used to seeing due to that easterly wind direction and extreme velocity. They’ll be stubborn and difficult to trigger but potentially large. Any avalanches this time of year on a thin snowpack can be particularly dangerous due to the many rocks and other obstacles lurking near the surface.
(11/24/2023)
Natural wind slab that did not run due to shallow slope angle. This is a good example of the potetnial size of the wind slabs that are sitting atop weak snow.
Photo: Travis Baldwin