Avalanche Forecast
Issued: Jan 21st, 2022 4:09PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs, Deep Persistent Slabs and Persistent Slabs.
Kate Ryan,
There is a special avalanche warning in effect for our area.
Rising freezing levels and solar radiation may trigger another large avalanche cycle this weekend.
Minimize your exposure to overhead avalanche terrain.
Summary
Weather Forecast
A drying trend is developing as a ridge of high pressure moves into the province today.Â
Tonight: mainly cloudy, no precip. Wind W-20km/h. Freezing level (fzl) 600m.
Sat: A mix of sun and cloud. Alpine High 0 C. Wind W-25 gusting to 50km/h. Fzl 1400m
Sun: A mix of sun and cloud. Alpine temperature: High 0 C. Wind W-25 gusting to 60km/h. Fzl 1500m
Snowpack Summary
Up to 20cm of new snow yesterday and warm temps have created fresh storm slabs over 2-4mm surface hoar (SH).
There are 2 PWLs in the mid-pack: SH is 50-80cm down at and below treeline + a layer of facets from Xmas is down ~100cm
The Dec 1 crust/facet combo is dn ~2-2.5m. This layer came alive last storm and will be a lingering concern for a long time
Avalanche Summary
A natural avalanche cycle occurred in the past 24 hrs with a notable size 4.0 off of Ross Peak that filled up the Elephant's Trunk up Loop Brook
A size 3 deep slab avalanche was triggered by a tree bomb on Abbott Wed
A widespread avalanche cycle occurred Mon. Size 3-4 avalanches occurred naturally and with artillery, some with crowns over 2m deep
Confidence
Freezing levels are uncertain
Problems
Storm Slabs
Up to 45cm of new snow, combined with warm temps and strong, gusty winds, are building fresh storm slabs. These may lie on a newly formed surface hoar or preserved stellar layer.
- If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.
- Convex features and steep unsupported slopes will be most prone to triggering.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Deep Persistent Slabs
The Dec 1 crust/facet combo came to life on Monday, resulting in numerous very large avalanches.
This is now a low probability/high consequence avalanche problem. It will be stubborn to trigger, but if it goes it will be huge.
- Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.
- Avoid thin, rocky or unsupported slopes.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Multiple persistent weak layers in skiable terrain awoke with Monday's storm. The Jan 11 surface hoar and New Years facets were the suspected failure plane for several avalanches that stepped down to the Dec. 1st crust/facet layer.
- If triggered the persistent slabs may step down to deeper layers resulting in very large avalanches.
- Be wary of slopes that did not previously avalanche
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 22nd, 2022 4:00PM
