Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
As you ascend into alpine terrain, your avalanche risk assessment should become more exacting. Terrain where wind and new snow have combined represents the greatest hazard of the day. Look for wind blowing snow, pay attention to where it's going and assess those slopes carefully. Over the past three days, wind has blown primarily out of the west, averaging 13 mi/hr with gusts to 42 mi/hr. Fresh snow still remains available for wind transport. Two days ago, a skier triggered wind slab was reported in near treeline terrain of the Castle Lake area. More of this is possible, as blowing and drifting of new snow continues. Wind will blow out of the north, cross-loading west and east aspects and directly loading southerly aspects. Remember that moderate wind speeds are much better and loading slopes than high winds. Slabs could be small to large and will exist on the downwind side of ridge features, gullies, rocky outcrops and other features that enhance wind loading. Use clues such as recent avalanches, snow surface cracking, drifts and snow surface texture to identify potentially unstable slopes, and consider avoiding them.
Example of a small wind slab in alpine terrain. If you see something like this, larger slabs could be possible.