Avalanche Forecast

Issued: Dec 17th, 2021 4:00PM

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

Avalanche Canada bchristie, Avalanche Canada

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 Sheltered areas with soft snow have the best riding, and the lowest avalanche hazard. Check for signs of instability like shooting cracks, whumpfing noises, or recent avalanches before venturing into bigger terrain. 

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

Generally unsettled weather persists with a bit of snow and moderate winds. Arctic air pushes in from the north on Saturday night.

Friday Night: Increasing cloud. Possible trace of new snow. Moderate to strong southwest winds, trending to moderate west at higher elevations. Treeline low around -16 °C. 

Saturday: Mostly cloudy. 2-7 cm of snow expected. Light to moderate northeast winds. Treeline high around -14 °C. 

Sunday: Cloudy in the morning, getting sunnier through the day. 0-5 cm of snow expected overnight, and a possible trace through the day. Moderate northeast winds with the possibility for strong winds at lower elevations. Treeline temperatures around -16 °C.

Monday: A mix of sun and cloud. No new snow expected. Moderate northwest winds, with possible strong winds at low elevations in the north end of the region. Treeline high around -17 °C.

Avalanche Summary

No new avalanches were reported on Thursday or Friday.

Wind slabs formed on all aspects in exposed terrain are expected to remain sensitive to human triggers.

Check out our forecaster blog for some thoughts on the snowpack at this point in the season. Persistent weak layers are still on our minds.

Snowpack Summary

Given the variable nature of the recent wind, slabs should be expected on all aspects in exposed terrain.

Check out this post from the Mountain Information Network (MIN) by our North Rockies field team for a great summary of conditions in Torpy on Thursday, and this post for Pine Bowl on Wednesday.

The mid and lower snowpack likely contains of a series of early season crusts which may have undergone some faceting. In the deeper snowpack areas of the region, these layers generally appear to have stabilized, but they still may be reactive in isolated areas, especially in places with a shallow snowpack.

Snowpack depth at treeline typically ranges from 50-250 cm, with the shallower value mainly on the eastern side of the range. The alpine snowpack typically ranges from 150-250 cm. 

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.

Problems

Wind Slabs

An icon showing Wind Slabs

These wind slabs have been less reactive in the last few days, but could still be triggered if you hit the wrong spot. 

Watch out for fatter looking pockets or pillows of snow, especially right at ridge-crests, or places where the terrain rolls away from you.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Dec 18th, 2021 4:00PM