Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
3-6 inches of new snow overnight, combined with strong SW winds, have created a fresh batch of wind slabs at middle and upper elevations. Slabs have formed over a variety of wet snow surfaces or crusts, so reactivity may vary from slope to slope. In general, expect these slabs to be larger and more widespread as you climb into the wind zone above 6000 ft.
Wind slabs often form on the downwind sides of ridges, below cornices, and underneath rock bands or on the aprons below gully features. You’ll want to use visual clues, such as blowing snow or surface textures, to help you identify where the problem lies. Small test slopes and quick snowpack tests can provide valuable data points about the reactivity of these slabs. Shooting cracks under your feet or machine are obvious clues you found an unstable slab and great reasons to default to lower-angled terrain out of the wind.
A cooling trend should help new snow accumulate on a favorable structure, but keep small storm slabs in mind if you find over 6-8 inches of new snow, particularly on steep or unsupported slopes.
(3/22/2025)
Signs like this are good reasons to steer around steep, wind-loaded start zones.
Photo: Joe Dellaporta