Avalanche Forecast

Issued: Dec 6th, 2020 4:00PM

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

Benjamin Firth,

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Winter is coming! Expect up to 25cm of new snow starting to fall Monday evening and continuing through late Tuesday afternoon.

Summary

Weather Forecast

Temperatures returning to seasonal normals. Snow beginning Sunday night and continuing through to Tuesday evening. 25cm of snowfall is forecasted for the next 2 days. Winds will increase and come from the SW during this period

Snowpack Summary

Previous winds have stripped the snow from all fetches in the alpine and open tree line creating slabs and cross loading in gullies and depressions. Warm temperatures have resulted in a melt freeze crust on solar aspects. Snow depth at tree line is up to 90cm with the Nov 4 crust down 50cm. Basal weakness continue to develop.

Avalanche Summary

Several wind slab avalanches have been observed on alpine NE aspects up to size 2 in the Jasper townsite area. No other avalanches observed or reported. No road patrols today

Confidence

Intensity of incoming weather systems is uncertain on Tuesday

Problems

Wind Slabs

An icon showing Wind Slabs

Widespread wind effect in the alpine and exposed treeline - highly variable with laminated slabs and bare ground. Be cautious of unsupported slabs.

  • If triggered the wind slabs may step down to deeper layers resulting in larger avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

The Nov. 4 crust is down about 50cm at tree line (2000m) and breaking down. Be careful around "thin to thick" areas where deep slabs could be triggered. Basal weakness continues to develop and could be reactive to large loads

  • Be cautious in shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Dec 7th, 2020 4:00PM