Avalanche Forecast
Issued: Jan 7th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs, Loose Dry and Deep Persistent Slabs.
aaron beardmore,
Parks Canada
The danger ratings are tightly coupled to snowfall amounts. The region can receive the forecasted 20cm and likely stay at considerable. However, if more snow than expected arrives the scales could tip to HIGH. Monitor local snow fall amounts.
Summary
Weather Forecast
Snowfall amounts on the latest models show 20cm by the end of day Thursday. The wind will peak tonight with gusts up to 80km/hr and then subside in to the moderate range, all coming from the West. The temperatures are expected to dive to the -20 on Friday.
Snowpack Summary
20-40 cm of snow, and strong wind from last few days have formed wind and storm slabs. At tree line, new snow sits on pockets of surface hoar in sheltered areas and sun crust on steep solar aspects. Generally, the upper snowpack of denser snow sits over a weaker lower snowpack consisting of facets, depth hoar and crusts.
Avalanche Summary
Third hand report of member of the public triggering a size 2 in the sunshine backcountry. No injuries or lost equipment reported.
Confidence
Forecast snowfall amounts are uncertain on Wednesday
Problems
Storm Slabs
An additional 20-30cm of snow Tuesday, Wednesday will add to the previous storm slab problem. At upper elevations this problem could be associated with additional load from moderate to strong winds.
- If triggered the storm slabs may step down to deeper layers resulting in large avalanches.
- Use caution in lee areas. Recent wind loading have created storm slabs.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Dry
While winds stay elevated and precipitation continues to come in, loose dry avalanches will be a problem in steep terrain. These small events can be enough to trigger a slab on slopes beneath cliffs or on ledges in gully features.
- Use caution above ledges and cliffs where small avalanches may have severe consequences.
- Be very cautious with gully features.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Deep Persistent Slabs
We have seen a few examples of these slabs becoming reactive during the storm. These large avalanches reach run out zones. As loading continues over the next few days, avoid exposure to overhead avalanche terrain.
- Avoid shallow snowpack areas where triggering is more likely.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 8th, 2020 4:00PM
