Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Steep slopes at higher elevations have been layered with drifted snow. These are the places where you could trigger an avalanche. Look for and avoid dense or hard snow below ridgelines and in spots downwind of terrain features. Avalanches you trigger in drifted snow can grow large as they step down to deeper weak layers, potentially taking the whole season's snowpack with it.
On February 20 and 22, backcountry snowboarders were caught and killed in avalanches in separate incidents. One west of the town of Silverton on a terrain feature locally known as The Nose. The other was near the summit of Berthoud Pass in a terrain feature locally known as The Fingers. In both fatal accidents, the avalanches broke several feet deep and spread wide across multiple terrain features. You can read the preliminary accident reports here andhere.