Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Snow has been drifting readily since Wednesday when a cold NE wind arrived. Snow surfaces likely consisted of sharp, faceted grains and now you might find areas of harder, wind packed snow. Be careful of reactive wind slabs, as instability may linger longer than expected through Friday. If you find fresh drifts that create shooting cracks when provoked, steer around pillows and drifts on steep slopes.
Look for wind rippled and stiffer snow surfaces, these will help pinpoint where you could trigger avalanches. Areas near ridgelines or pronounced ribs may be especially prone to drifting. Slopes beneath large cliffs also tend to harbor slabs, as loose snow spindrifts off and accumulates below. You can use small test slopes to check how easily the snow fractures. You can also choose slopes less than 30 degrees or look for wind-sheltered terrain to avoid this problem.
Example windslab avalanche that ran on the 1/31 crust from last week. Copper Creek, SE, 7200ft
Photo: Harry Keane