Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Recent reports of wind-affected snow have mostly featured thin crusts and hard slabs from previous southwesterly winds. Slabs have been isolated, small in size, and unreactive to the weight of a rider aside from an intentionally triggered slab in the Northern Whitefish Range.
Winds shifted to northeasterly yesterday morning but tapered throughout the day. Observations did not notice any blowing snow onto southwesterly slopes. Wind speeds could increase throughout the day and/or change directions. Expect to find fresh wind slabs where the snow isn't locked down by surface crusts especially if you notice blowing snow.
Identify areas of wind-affected snow by their rippled surface texture or dune shaped features. Look for these clues along exposed ridges, below saddles and further down-slope in cross-loaded gullies. Soft slabs cracking around your feet or machine indicate that slides are possible on steep slopes. Hard slabs can support the weight of a rider and have a hollow, drum-like sounds. They may not provide clear signs of instability and can break wider than expected or well above you. Move to less steep, or more sheltered terrain to avoid these hazards.
(1/16/2025)
The debris of an intentionally triggered soft slab on a wind-loaded slope.
Photo: Ryan Minton