Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 2
Human-triggered wind slab avalanches remain possible today, especially on exposed, upper-elevation slopes where snow has been recently drifted by wind. Cornices built by storm winds may break farther back than expected and could trigger avalanches on the slopes below.
- Watch for signs of wind drifts such as rounded, pillow-like features, chalky or stiff snow, hollow or drum-like sounds, and cracking underfoot.
- Softer, newly formed wind slabs are generally easier to trigger, while older, harder slabs can be more deceptive— sometimes allowing people to travel well out onto them before failing suddenly.
- Avoid travel on or beneath cornices and on steep slopes with stiff deposits of wind-drifted snow.
We have not seen recent avalanches failing on buried persistent weak layers (aside from a small slide in Miller Bowl), and snowpit tests continue to show improving stability. However, poor snowpack structure still exists in isolated, steep, rocky terrain with a shallow snowpack. In these areas, a wind slab avalanche could step down into older weak snow, resulting in a much larger and more dangerous slide.
Just to the south of our zone, a snowmobiler triggered a sizeable wind slab avalanche on Whiskey Hill in the Monte Cristo area yesterday. The rider was able to ride off to the side, and luckily so, as they did not have avalanche rescue equipment. (PC: Brackelsberg)