Avalanche Forecast
Issued: Dec 23rd, 2019 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.
william lawson,
Parks Canada
Avalanche control on Mt. Stephen, Mt Field and Mt Dennis. Please avoid any activity in these areas.
Enter terrain very cautiously and avoid exposure to overhead hazard. Avalanche conditions will take some time to improve.
Summary
Weather Forecast
Temperatures will cool over the next few days with lows dipping down to -20C. Lingering moisture will leave us with mostly overcast skies and light flurries Tuesday. Upper elevation wind values will continue to be in the light to moderate range.
Snowpack Summary
30-60cm of settled storm snow has formed storm slabs all elevations and aspects. At upper elevations evidence new wind transport is visible. Below the new snow the snowpack structure is generally weak, consisting of facets and depth hoar and a Nov crust up to 2500m. These weak layers are getting overloaded with all of the new snow.
Avalanche Summary
Widespread natural avalanche activity to size 3 on all aspects and elevations is mostly 24-48 hours old. Explosive control today continued to produce large avalanches to size 3 running full path. Evidence of light loads initialing large slabs has shown that the snowpack is primed for triggering.
Confidence
Problems
Storm Slabs
Storm slabs continue to be reactive Monday. We are seeing widespread avalanche activity releasing from this new load. As the storm snow settles over the next few days natural activity will lessen. Human triggering likely persist for much longer.
- If triggered the storm slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Deep Persistent Slabs
The weak, faceted mid and lower pack is overloaded by the new storm snow at all elevations. Avoid exposure to any large overhead hazard.
- Be aware of the potential for full depth avalanches due to deeply buried weak layers.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 24th, 2019 4:00PM
