Avalanche Forecast
Issued: Dec 1st, 2021 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.
Timothy Johnson,
Maligne Lake Road and the Icefields Parkways are both currently closed. The Icefields Parkway could open from Jasper to Parker Ridge late Thursday morning. Check Alberta 511 for updates. This new snow will take time to settle so keep it conservative.
Summary
Weather Forecast
Thursday: A mix of sun and cloud.
Alpine temperature: High -9 C.
Ridge wind west: 20 km/h gusting to 50 km/h.
Freezing level at valley bottom.
Friday: Cloudy with sunny periods and isolated flurries.
Precipitation: Trace.
Alpine temperature: Low -16 C, High -13 C.
Mostly light ridge wind occasionally gusting to 35 km/h.
Freezing level at valley bottom.
Snowpack Summary
About 30 cm of storm snow fell in the last 24hrs in the Parker Ridge area. About 20cm of new snow around Maligne Lake. Freezing level is about 2100m with the snow line around 1200m. The mid-pack is around 80cm thick above a thin crust near the ground in some locations. Snowpack is shrinking rapidly at lower elevations.
Avalanche Summary
Multiple, natural wet loose avalanches up to Size 2 observed on the Icefields Parkway early in the storm. We can expect more have run since the storm started.
Confidence
Due to the number and quality of field observations
Problems
Storm Slabs
We can expect storm slabs in the trees and in non wind affected tree line locations. In the alpine with strong SW winds we can expect wind slabs to be forming.
- Avoid avalanche terrain during periods of heavy loading from new snow and wind.
- 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 average 1 meter snowpack has a crust near the ground surrounded by weakening large grain facets. This is a layer to watch as our neighbors are experiencing activity on it.
- Avoid thin rocky or unsupported terrain features.
- Use caution on open slopes and convex rolls
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 2nd, 2021 4:00PM
