Regions
Northwest Inland.
Watch for wind slabs lurking in unusual places as the wind shifts direction.
Confidence
Poor - Due to the number of field observations
Weather Forecast
Lingering flurries will die out on Sunday, then it becomes cold and clear with strong outflowing N-NE winds.
Avalanche Summary
A naturally-triggered size 1.5 wind slab was observed at treeline on a north aspect in the Hankin area. It is suspected to have failed on Wednesday or Thursday. On Tuesday we received a report of a size 1.5 skier remotely triggered avalanche in the far north of the region. It released on a steep, wind loaded feature and was triggered from 5m away. The 25-45cm thick slab occurred around 1600m elevation.
Snowpack Summary
10-20 cm new snow from Friday night may have buried old wind slabs. New wind slabs are likely to form on south to west-facing slopes as winds shift into an outflow pattern. A layer of buried surface hoar down about 30-50 cm appears to be spotty in distribution, but may still be a concern in some areas. Near the base of the snowpack, the mid-November crust-facet layer has become less likely to trigger but is still in the back of our minds.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.