Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 3
Most natural avalanches in the Logan Zone occur during significant winter storms, but most accidents seem to happen when the weather clears, right after the storms. Heavy snowfall and westerly winds during the storm added weight to, and probably overloaded slopes with poor snow structure that were already near the tipping point. Buried persistent weak layers consisting of sugary faceted snow are widespread across the Logan Zone, and the threat of large and deadly avalanches failing on weak snow near the ground remains quite real.
- Avalanches failing on a buried persistent weak layer might be triggered remotely, from a distance, or worse from below!
- Cracking and collapsing of the snow are a red flag, indicating unstable snow conditions.