Avalanche Forecast

Issued: Nov 21st, 2019 8:00AM

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

Parks Canada mike smallwood, Parks Canada

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The new Winter Permit System is in effect.

Ensure you have a permit to enter restricted areas when they are open.

Be alert for persistent slabs and early season terrain traps.

Summary

Weather Forecast

Sunny skies today with light N'ly winds and freezing levels rising to 1800m. High pressure continues on Friday with freezing levels to 1000m and winds picking up to moderate from the SW. Heavy snowfall is expected to arrive on Saturday along with increased SW winds.

Snowpack Summary

A 35-50cm persistent slab sits on a crust/surface hoar/stellar layer. Below this are several melt-freeze crusts from late October. Tests are showing easy to moderate results on the persistent slab, indicating they are easily triggered by human loads.

Avalanche Summary

Human-triggered avalanches to size 2 were reported from Little Sifton, Balu Pass and the Asulkan Hut area this week. The Balu Pass avalanche buried the person to their neck and gear was lost. Numerous natural avalanches to size 2.5-3 were observed from The Dome, Tupper, MacDonald, and Cheops during the storm Sunday morning.

Confidence

Problems

Persistent Slabs

An icon showing Persistent Slabs

The persistent slab sits atop a crust/surface hoar/stellar layer. This is an ideal sliding layer for this avalanche problem. Warm, direct sun with rising freezing levels may be a strong enough trigger to start an avalanche.

  • Use caution in lee areas. Recent wind loading has created wind slabs.
  • Minimize exposure to terrain traps where the consequences of an avalanche could be serious.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Nov 22nd, 2019 8:00AM