Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Strong winds will easily transport new snow and build firmer slabs over the latest April crust. If you see cracking in the new snow, feel stiff or hollow snow near the surface, or see natural avalanches, these are red flags that you could trigger an avalanche on similar slopes. There's some uncertainty about whether or not small wind slabs will develop on open slopes below treeline, so keep your tabs on conditions as you change aspects and elevations during the day. To avoid triggering a wind slab, steer around steep open lee slopes, sticking to lower angled and wind-sheltered terrain.
By the end of the day, you may encounter up to a foot of new snow in some areas of the mountain below treeline. With April showers comes the chance of graupel or soft hail. These are additional inter-storm layers that storm slabs can fail on. Use care on very steep slopes to avoid getting surprised by a small dry loose or storm slab avalanche.
The weather alone will make for difficult travel at upper elevations. Commit to a safe return by knowing your route and factoring in for periods of poor visibility and cold temperatures/low wind chills if you venture above treeline Saturday. Avalanche danger will likely increase Saturday night into Sunday with more cold snow and wind in the forecast.
Example of a small intentionally triggered avalanche in Salmon River in wind-drifted snow (6200ft, SE).
The avalanche was triggered by a skier from a short distance away on the low-angled ridge.
Photo: Andrew Kiefer