Avalanche Forecast
Issued: Mar 1st, 2021 4:32PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
Barb Sharp,
Forecasted snowfall and continued wind will increase the load sitting on the faceted snow pack. Avoid wind-loaded features.
Summary
Weather Forecast
Overnight: 9cm of snow forecast for overnight Monday to Tuesday morning, with moderate to strong SW winds.
Tuesday: Alpine temperature: High -8 C. Ridge wind southwest: 25 km/h gusting to 75 km/h. Trace amount of snow
Wednesday: Alpine temperature: Low -11 C, High -6 C. Ridge wind southwest: 20 km/h gusting to 50 km/h. Trace amount of snow.
Snowpack Summary
Continued widespread wind effect in open areas at all elevations. Windward aspects have been heavily stripped of snow. The snowpack is highly variable. Shallow snowpack areas are weak and failing in compression tests, while the mid-pack is supportive in areas where the snowpack is deeper.
Avalanche Summary
A few wind slabs size 2-3 were observed today in the Sunwapta Zone on E and SW aspects; 2 of these avalanches were triggered by cornice failures and stated at or just above tree line, running to below tree line.
Confidence
Problems
Wind Slabs
Continued wind slab development is expected with overnight snowfall and moderate SW winds.
Wind slabs in the alpine and exposed treeline features have the potential for wide propagations across connected features.
- Be aware of the potential for wide propagations due to the presence of hard windslabs.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Caution in thin facetted snowpack areas where triggering is more likely. This is a low probability but high consequence problem.
- Avoid shallow snowpack areas where triggering is more likely.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 2nd, 2021 4:00PM
