Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
On Friday, I was able to poke around in the alpine and assess how the snowpack is looking after our recent storm cycle. I observed several crowns from natural slab avalanches above treeline on steep terrain that faces NE - SE. Most of these naturals were on steep unsupported terrain, or steep slopes underneath cliff bands. Although I did not encounter any reactive wind slabs during my tour, wind slab presence on leeward slopes indicated the existense of poor snow structure in these specific areas. With a couple days of calm-light winds and relatively warm weather, these slabs are gaining strength and moving into the stubborn category for Saturday. That being said, isolated terrain with larger accumulations of wind drifted snow could result in large avalanches if you were to trigger a slab.
If you find yourself traveling on terrain with wind drifted snow, monitor the depth of recently formed wind slabs to gain a better understanding of how large an avalanche could be. Signs of unstable snow such as shooting cracks are indicators that the snow is currently unstable and you could trigger a slide. Use small, no consequence indicator slopes to assess terrain before stepping out to consequential steep slopes. Remember, you can always avoid wind loaded slopes if you are unsure of stability.
(1/9/2026)
Several crowns on NE face of Middle Sister from natural avalanche activity during recent storm cycle.
Photo: Ryan Marvin