Storm Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1–2
On Monday, you are dealing with two different versions of the same avalanche problem. Continued snow and wind will create small fresh slabs that are likely to be sensitive to your weight, especially in the morning until the snow shuts off. You are more likely to trigger these slabs in wind-loaded areas and in convex and unsupported terrain. But what makes this problem worse is what it’s hiding underneath.
The new snow is falling on existing slabs up to 3’ deep that are reactive and capable of propagating wide, long-running, and dangerous avalanches. This problem is buried by the new snow, so you won’t be able to assess it by looking at the surface. It will be most dangerous on steep, exposed slopes that were wind-loaded over the weekend, but those same slopes may now have a soft, fluffy, and inviting cap from the new snow. Don’t believe it. You may not get any warning signs before triggering a large avalanche.
This problem may be tricky to explain, but it is simple to manage.
Monday isn’t the day to trust steep, open slopes. Don’t worry about identifying the problem, just choose sheltered, lower-angled terrain. If you do venture into steeper sheltered slopes, carefully assess the bond of the new snow before committing. Look for hard-over-soft snow and use tools like uptrack tests, small test slopes, and hand shears to help evaluate conditions.
(12/15/2024)
This 2 foot deep wind slab avalanche was triggered by an explosive during control work by the Crystal Pro Patrol. It broke within old snow above the 12/7 interface.
Photo: Crystal Pro Patrol