Avalanche Forecast
Issued: Dec 10th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Deep Persistent Slabs.
Stephen Holeczi,
There is uncertainty about what problems exist in Little Yoho due to lack of observations. Of note, small avalanches can run far due to the layer they are sliding on, and as the new snow starts to facet. Likely good ski quality!
Summary
Weather Forecast
High pressure will continue Friday with light winds, and no snow. Temperatures will continue to stay cool in the valley bottoms and in the alpine (-15C)
Snowpack Summary
20-40 cm of low density new snow sits on the december 7th layer of sun crust, facets or surface hoar depending on your location. This new snow came with minimal wind and seems less reactive than we had thought it might be. At the bottom of the snowpack, the Nov. 5th crust / facet layer persists. Snowpack depths are 90-150 at treeline.
Avalanche Summary
Limited observations from Little Yoho region. No new avalanches reported.
Confidence
Problems
Storm Slabs
In general there is more storm snow overlying the Dec 7 layer of surface hoar, facets, and sun crust depending on aspect and elevation. In particular, there was large surface hoar noted prior to the last storm.
- Dig down to find and test weak layers before committing to a line.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Deep Persistent Slabs
The Nov 5 crust has facets above and below it, and exists up to 2500m on shady aspects and higher on solar aspects. We haven't seen any activity on this layer since the storm, but the new load may have made it more reactive in some areas.
- Be aware of thin areas that may propogate to deeper instabilites.
- Pay attention to overhead hazards like cornices which could trigger the deep persistent slab.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 11th, 2020 4:00PM
