Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2.5
What and where is it: After several days of snowfall and strong west/northwest winds, large wind slabs primarily on northeast, east, and southeast aspects may appear stubborn but remain sensitive to a human trigger. New snow from last night and today, combined with southwest and west winds, may build softer, more reactive wind slabs on top of the older slabs.
How can you recognize it: With good visibility, wind slabs can be identified as areas of smooth, rounded snow that may be several feet thick. While traveling, watch for snowdrifts deeper than your boot tops, as this is a sign that you've encountered a wind slab. New wind slabs will be softer, look for shooting cracks and actively drifting snow as a red flag. The older slabs are larger, and won’t give much feedback as to reactivity without digging. Use your hand, shovel, or ski pole to assess the depth and structure of these slabs. A stronger, denser layer of snow over a softer, weaker layer indicates instability. Be sure to frequently assess the snowpack as you travel, as it can vary significantly - even within the same slope. How can you manage it: Actively look for areas of newly drifted snow and avoid deep drifts to limit your exposure to avalanche hazards. Today, the wind slab avalanche problem is likely to be smaller and less consequential on west-facing aspects. If you're uncertain about the sensitivity or location of wind slabs, consider taking an alternate route through simpler, low-angle terrain.