Avalanche Forecast
Issued: Jan 21st, 2025 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
Avalanche Canada,
Avalanche Canada
Make conservative terrain choices due to a reactive buried weak layer, along with ongoing wind and storm slab formation throughout the day on Wednesday.
Summary
Confidence
Moderate
Avalanche Summary
Avalanche activity on the early December weak layer has steadily decreased in frequency since late last week, but it remains a significant concern. The most recent event, a remote-triggered size 2 avalanche on Sunday, underscores that despite the decreasing frequency, the layer remains reactive in certain terrain features. Reports of large avalanches (size 2 and greater), including remote triggers, over the past week emphasize the ongoing instability of this layer.
Snowpack Summary
Snow on Wednesday will accumulate atop previously wind-affected storm snow. A layer of surface hoar, facets, or a thin crust exists in wind-sheltered areas up to 75 cm below the surface. Reports suggest this layer is bonding well.
The current layer of concern is buried roughly 100 to 200 cm deep - surface hoar, facets, and a crust. This layer produced large natural avalanches during the recent storm and continues to be sensitive to triggering.
Weather Summary
Tuesday Night
Mostly cloudy with snow beginning early in the morning. 20 to 40 km/h southwest ridgetop wind. Treeline temperature -8 °C.
Wednesday
Cloudy with 10 to 25 cm of snow. 40 to 50 km/h southwest ridgetop wind. Treeline temperature -8 °C.
Thursday
Cloudy with up to 5 cm of snow. 40 to 50 km/h west ridgetop wind. Treeline temperature -6 °C.
Friday
Mostly cloudy. 30 to 40 km/h northwest ridgetop wind. Treeline temperature -6 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Remote triggering is a concern; avoid terrain where triggering overhead slopes is possible.
- Pay attention to the wind; once it starts to blow, sensitive wind slabs are likely to form.
- Choose low-angled, sheltered terrain where new snow hasn't been wind-affected.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
Problems
Storm Slabs
Be alert to wind and storm slab formation throughout the day on Wednesday with new snow and increasing winds. Small surface avalanches have the potential to step down to deep weak layers producing larger than expected avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
A thin crust along with surface hoar and/or facets buried in early December persists roughly 100 to 200 cm deep. It appears to be of greatest concern in areas with shallow snowpacks and on wind-loaded north or east-facing slopes.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 22nd, 2025 4:00PM
