Avalanche Forecast
Issued: Jan 14th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Adam Greenberg,
Wednesday's storm has formed widespread wind slabs at upper elevations, and a breakable crust below treeline. Choose moderately angled terrain with low consequence, avoid walking under cornices, and travel downhill through the burnt forest with care.
Summary
Weather Forecast
Friday: Cloudy with sunny periods and an alpine inversion. Strong to Extreme W winds, alpine high 0 early in the morning dropping to -5 in the afternoon
Saturday: Mainly cloudy with isolated flurries. Moderate NW winds, inversion with alpine high of -5
Sunday: Cloudy with flurries. Inversion breaking down during the day, with strong to extreme W wind
Snowpack Summary
The storm brought 30cm of new snow. Upper elevations are heavily wind affected, and new windslabs will be found in lee areas. Below 1900m rain during the storm formed a breakable crust which can be found under 5cm of fluff. The Dec 9th crust can be found down 70-100cm at Cameron Lake. Areas east of the divide hold a thin & faceted snowpack.
Avalanche Summary
Good visibility on Thursday showed a widespread avalanche cycle in most wind loaded features from Size 1 to Size 3 that occurred on Tuesday night/Wednesday morning. A couple of these involved step down avalanches to deeper weak layers, including a size three with impressive propagation in a thin convexity in Rowe Bowl.
Confidence
The weather pattern is stable
Problems
Wind Slabs
New snow combined with strong winds has formed slabs which will take time to heal. Choose conservative terrain.
- Choose low angle and supported terrain. Avoid large features.
- Use caution in lee areas. Recent wind loading has created wind slabs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Isolated persistent slab avalanches were observed after the last storm. This a reminder that they can still be triggered by cornice fall or smaller avalanches stepping down in thin snowpack areas.
- Pay attention to overhead hazards like cornices which could trigger the persistent slab.
- If triggered the wind slabs may step down to deeper layers resulting in larger avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 17th, 2021 4:00PM
