Avalanche Forecast

Issued: Mar 1st, 2021 4:32PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Wind Slabs and Deep Persistent Slabs.

Barb Sharp,

Email

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

Intensity of incoming weather systems is uncertain

Problems

Wind Slabs

An icon showing 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

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

An icon showing 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

Unlikely - Possible

Expected Size

1.5 - 3

Valid until: Mar 2nd, 2021 4:00PM

Login