Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1–2
Dangerous avalanche conditions exist. You can easily trigger an avalanche where you find 8 inches or more of new or drifted snow on slopes steeper than around 30 degrees. Avalanches triggered in the new snow may gouge into old, weak snow and become large enough to bury you. The most dangerous slopes face the north half of the compass, where the new snow forms a cohesive slab over weak older snow. Also, look for and avoid areas of wind-drifted snow above treeline, especially on northeast, east, and southeast-facing slopes below ridgetops and in cross-loaded terrain features.
If you experience cracking or collapsing in the new snow, avoid traveling on or under steep slopes because there is a chance you could trigger avalanches from a distance or from below. Even triggering an avalanche on a small slope could be dangerous if it sweeps you into a terrain trap like a gully, bench, or rocks and trees. Avalanche conditions are the most dangerous we’ve seen in a month.