Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 2
Natural cornice fall triggered at least two large wind slab avalanches between Friday afternoon and Saturday afternoon in the Hurricane Ridge area. Avoid steep open slopes directly below ridgelines where you find firmer wind drifted snow and avoid lingering below slopes with large overhanging cornices. Whether triggered naturally or by backcountry travelers, these slab avalanches can break down to recent storm layers and become large enough to bury, injure or kill you. You can stick to lower angle slopes not capable of producing large avalanches. You are most likely to trigger a wind slab avalanche on northerly aspects near and above treeline.
Large cornices have formed along ridgelines following several days of stormy weather. Be mindful of parties below you if traveling along ridgelines. Make sure to give cornices a wide berth as they often break back further than you expect. With high freezing levels in the forecast, cornices may fail naturally again on Sunday.
(1/8/2022)
Crown (red line) of a large avalanche on North Bowl in Hurricane Ridge area that released sometime Friday afternoon - Saturday (1/8). The avalanche was likely triggered by natural cornice fall. Estimated by NPS: HS-NC-R3/D2.5, northerly asp 5300'.
Photo: ONP Rangers