Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–1.5
Wind slabs may remain sensitive to human triggers.
Wind slabs likely remain triggerable in steep or convex terrain features and near ridgetops.
Wind slabs may remain sensitive to human triggers.
Cornices overhead are a primary concern during sunny, warm, or windy conditions. Cornice failures are dangerous on their own, but they also have potential to trigger large persistent slab avalanches that would otherwise be difficult to trigger.
Saturday night: Mostly cloudy, a trace of snow, moderate northwest wind, freezing level dropping to valley bottom.
Sunday: A mix of sun and cloud, light northwest wind, high of -4.
Monday: Sunny, moderate northeast wind, high of -13.
Tuesday: Increasing cloud, flurries, strong northwest wind, high of -12.
Natural and skier triggered wind slabs were reported up to size 1.5 on Thursday. On Friday, a single skier triggered size 1 wind slab was reported on a wind-loaded convexity near ridgetop at treeline.
10-20 cm of recent snow sits over a 10-20 cm thick, supportive rain crust. At upper elevations the recent snow has been extensively wind affected, with exposed windward features scoured down to the crust. Below 1300 m, moist surfaces will refreeze as temperatures drop this weekend.
The thick rain crust effectively caps the underlying snowpack, making human triggering of avalanches on weak layers deeper in the snowpack very unlikely. Large cornice failures may still have potential to trigger these deeper layers.