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Summary
Confidence
Moderate - Due to the number of field observations
Weather Forecast
MONDAY NIGHT: Cloudy with clear periods. Light south wind. Freezing level valley bottom.TUESDAY: Mix of sun and cloud. Light west wind. Freezing level valley bottom.WEDNESDAY: Cloudy with isolated flurries, trace accumulation. Light southwest wind. Freezing level valley bottom.THURSDAY: Mix of sun and cloud. Light southwest wind. Freezing level valley bottom.
Avalanche Summary
On Sunday, explosives and skier traffic triggered wind slab avalanches to size 2. Several explosives triggered avalanches to size 2.5 were reported in the region on Saturday. One natural size 2 avalanche that was triggered by a cornice was reported in the region on Friday.
Snowpack Summary
On Sunday, strong to extreme winds redistributed recent snow and formed wind slabs. In total, 60-90 cm of recent snow has formed a slab that sits on a persistent weak layer of facets (sugary snow) that formed during the dry weather in early December. Though avalanche activity on this layer has slowed down in recent days, it may still be easy for humans to trigger avalanches on this layer in certain terrain features. Steep features where the underlying ground cover is smooth, places where the snowpack depths are variable, and large convex features are some of the more likely places to trigger this layer.The lower snowpack has a weak structure composed primarily of facets. It is likely that an avalanche triggered on the persistent slab would step down to the lower facets, resulting in a full depth avalanche.
dsaly,
Avalanche Canada
