Avalanche Forecast
Regions: Bonnington, Crawford, Grohman, Kokanee, Kootenay Pass, Moyie, Norns, St. Mary, Valhalla, Ymir.
Recent storm snow needs time to gain strength and stabilize, while a buried crust remains a major concern.
Confidence
Moderate
Avalanche Summary
A remotely triggered size 3 avalanche was triggered on Monday just west of Kimberley. The avalanche was triggered from a ridgetop approximately 20 m away, propagated roughly 300 m, and was 30 cm deep on average. It is suspected this slide occurred on the buried crust/facet layer.
Numerous natural, skier, and explosive-triggered avalanches occurred on Sunday throughout the region. Avalanches occurred in upper treeline and alpine terrain on various aspects, sized 1 to 2.
Snowpack Summary
The recent storm brought significant snowfall at higher elevations, which has been redistributed by strong alpine winds. Around 30 cm of snow now sits atop a variety of preexisting surfaces in the upper snowpack. These surfaces include sun crusts on south-facing slopes and faceted snow or surface hoar in sheltered, north-facing terrain.
A widespread crust exists down roughly 50 to 80 cm. In many areas, small, weak faceted grains have formed just above or below this crust.
The mid and lower snowpack is generally well settled.
Weather Summary
Monday Night
Partly cloudy with 0 to 2 cm of snow. 20 to 30 km/h west ridgetop wind. Treeline temperature -12 °C.
Tuesday
Sunny with cloud building in the afternoon. 20 to 30 km/h southwest ridgetop wind. Treeline temperature -12 °C.
Wednesday
Cloudy with 5 to 20 cm of snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -4 °C. Freezing level 1500 m.
Thursday
Cloudy with 10 to 20 cm of snow. 40 to 60 km/h southwest ridgetop wind. Freezing level 1500 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Good day to make conservative terrain choices.
- Give the new snow several days to settle and stabilize before pushing into bigger terrain.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Avoid areas where the snow feels stiff and/or slabby.
Avalanche Problems
Storm Slabs
Recent snow and wind have created cohesive slabs that may sit atop a variety of weak layers and good sliding layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2.5
Persistent Slabs
A widespread crust exists down roughly 40 to 80 cm. This is a particular concern in areas where weak faceted grains have formed above or below the crust. This layer may become more triggerable with increased snow depth and weight above.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 2 - 3