Wind Slabs
- Hochgebirge
- Waldgrenze
- Unterhalb der Waldgrenze
- Wahrscheinlichkeit
- Likely
- Größe
- 2
Drifting of the new snow by strong southerly winds created wind slabs on the lee side of major ridges and in and around terrain features like sub ridges, gully walls, mid-slope roll-overs, and under cliff bands. People could trigger wind slab avalanches on steep slopes, mainly on the north half of the compass. Even small avalanches of stiffer, wind-drifted snow could run fast and far on the slick crust formed during last week's warm temperatures.
- Avoid recent drifts or wind slabs on steep slopes. Wind slabs are made up of stiffer snow that may be more supportable than the surrounding powder. Lense-shaped drifts often make hollow, drum-like sounds.
- Cracking is an obvious sign of wind slab instability.
- Soft slab avalanches of new snow are possible on slopes steeper than 30° at all elevations.
Although unlikely, hard slab avalanches failing on a buried persistent weak layer may be reawakened by a load of drifted new snow, and these avalanches could be large and life-threatening. Avalanches failing on a persistent weak layer are possible in recently drifted outlying rocky or windswept areas with generally shallow snow cover. Collapsing or whumpfs are obvious signs of instability, but these red flags may not be present when deep hard slab avalanches occur.
- It's a good idea to get your shovel out and dig into the snow to identify areas with poor snow structure before you commit to steeper objectives.
