South Rockies

Good

Unsettled weather is bringing few flurries and cloudy skies overnight into Thursday morning. An upper ridge building over the coast will host a clearing drying trend, with cooler temperatures. Thursday: Cloudy with sunny breaks in the afternoon. Moderate West winds are expected and alpine temperatures near -12. Freezing levels should remain at Valley Bottom through the forecast period.Friday/Saturday: Cloudy with few flurries and some sunny breaks. Ridgetop winds will be light-moderate from the West, and alpine temperatures near -15.

On Sunday afternoon skiers triggered a size 3.0 slab avalanche from the ridgeline off Mt. Fernie. The initial trigger was a smaller wind slab which then stepped down to a deeply buried rain crust. There were no human involvements. For further details, please visit the Incident report here:  https://avalanche.ca/cac/library/incident-report-database/view.No new observations from Wednesday.

The average storm slab depth is approximately 20 to 50 cm, and may be sensitive to rider triggers; especially in areas that host more of a wind slab problem (lee slopes and behind terrain features (spines, gullies, ridgelines). Two crusts have been identified in the snowpack: one close to the ground that formed in early November and one around 90-140 cm below the surface, which formed in early December. Recent snowpack tests done on the December crust from the Harvey Pass Riding Area showed a moderate compression test failure, with a sudden collapse characteristic. The testing done on that layer showed inconsistent results. Recent compression and deep tap tests done in the Lizard Range have shown hard results. This layer may be difficult to trigger, especially in deeper snowpack areas. However, if triggered, a large and destructive avalanche would occur. The mid pack is generally well settled throughout the region.