Avalanche Forecast

Issued: Dec 24th, 2021 3:00PM

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

Avalanche Canada mkoppang, Avalanche Canada

Merry Christmas! Light snowfall and cold temps will continue over the next few days! Watch for slabs in the upper snowpack as you transition into open wind affected areas.

Summary

Confidence

High - The number, quality, or consistency of field observations is good, and supports our confidence.

Weather Forecast

Temperatures will continue to drop over the next few days with lows around -26C on Christmas day and around -30C on boxing day! Winds will continue to be light and variable with snowfalls of around 10-12cm over the next 48hrs.  

Avalanche Summary

No new avalanches were observed on Friday but visibility was limited. Field teams in the Commonwealth area didn't see anything during there tour.  

Snowpack Summary

Light snow continued on Friday with accumulations of around 5cm. Up to 30cm of recent storm snow has fallen with variable winds. Windslabs and storm slabs can be found in the upper snowpack at treeline and above. These slabs are beginning to settle and were not reactive to ski cuts on Friday at 2400m but suspect they are still reactive in Alpine areas where the winds have been stronger of late. Aside from the new surface instabilities, we are also seeing a distinct change in the Dec 1 crust character. It is breaking down, and in doing so, its forming a layer of facets immediately above the crust. This facet layer is down 70-85cm, widespread up to 2300m and so far failing in the hard range with tests. In other words, it's down there brewing and we can expect the scales to quickly tip as the new snow load increases. 

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Be especially cautious as you transition into wind affected terrain.
  • Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.

Problems

Wind Slabs

An icon showing Wind Slabs

Windslabs are being found in alpine terrain and in specific features at treeline such as gullies. They are begginning to settle but still reactive in steeper terrain. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Storm Slabs

An icon showing Storm Slabs

Storm slabs are being observed at treeline areas where storm snow was deepest

Aspects: All aspects.

Elevations: Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 25th, 2021 3:00PM