Wind Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1–2
When the storm tapers off around midday, 6-8 inches of new snow will likely have accumulated since yesterday morning. In the eastern portion of this zone—in the Little Wood Drainage and near Mormon Hill—upwards of a foot of new snow has fallen. This new snow has been blown around by winds from a variety of directions—from the S, SE, SW, and W. As a result, expect to find fresh wind drifts on a variety of aspects at higher elevations and in open, wind-exposed terrain. What's more, some of these wind drifts will be forming on weak, faceted snow surfaces that formed during the recent dry weather, and could be easily triggered by your weight. A skier on Galena Summit yesterday remotely triggered a small wind slab avalanche that released on this touchy old snow surface. These wind slabs will continue to build through the day, and triggering one may produce an avalanche large enough to bury you.
After a long period of relatively stable conditions, it's time to get our heads back in the game. Scale back your terrain choices by avoiding steep, upper elevation, wind-exposed terrain. Be sure to leave your Low danger sunglasses at home, and keep your avalanche eyeballs peeled for obvious signs of instability such as natural slides, cracking of the snowpack, and slopes with wind-drifted or pillowed snow.
ADDITIONAL DISCUSSIONThe eastern portion of this zone—in the Little Wood Drainage and near Mormon Hill—have received upwards of 12 inches of new snow since yesterday morning. Expect wind slabs to be larger and more dangerous, and it may be possible to trigger slab avalanches involving the storm snow even on wind-sheltered slopes. Use extra caution in this portion of the zone, where the danger may be approaching HIGH.