Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 3
It’s been two weeks since the last storm and avalanche cycle. Buried persistent weak layers are slowly adjusting to the load and are becoming more stubborn to trigger. Obvious red flags like collapsing and cracking have faded, but the underlying snowpack structure remains poor. The danger has dropped to moderate, but the consequences of triggering an avalanche remain severe.
On northerly aspects near and above treeline, thick hard slabs—2 to 4 feet deep—rest on top of these persistent weak layers. This is a highly unpredictable setup, and committing to steep slopes with this structure is a gamble. If triggered, avalanches could step down and take out the entire season’s snowpack.
Thin, rocky areas, steep convex rollovers, and slab margins remain likely trigger points. When the payoff for riding steep terrain is minimal, it’s hard to justify the risk. Our approach continues to be simple: avoid steep slopes in this terrain altogether.
I shot this video last Sunday while we were still at considerable danger. We have since moved into moderate but there are some salient points to take home.
