Avalanche Forecast

Issued: Dec 28th, 2020 3:00PM

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

Avalanche Canada JMackenzie, Avalanche Canada

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Watch for buried wind slabs on all aspects at higher elevations. Dig and explore the slab properties often as there is a lot of variability in the region's snowpack.

Summary

Confidence

High -

Weather Forecast

Tuesday will be mainly sunny with light NW winds. Cold temperatures overnight with a daytime high near -11 at Treeline. Wednesday may bring some light flurries, but accumulations will be minimal.

Avalanche Summary

Isolated loose dry avalanches up to size 1 were observed in steeper Alpine terrain on N and E aspects.

Snowpack Summary

Up to 15cm of recent snow overlies a variety of previous surfaces. This surface snow is soft and fluffy in some areas, and wind affected in others, especially as you transition to the Alpine. Extensive wind slabs were formed in the pre-Christmas storm, and it is worth noting that the storm arrived with extreme Northerly winds, which switched to extreme SW winds in the following days. Therefore, the region has buried wind slabs on virtually all aspects. The depth and character of these slabs is highly variable, and it is worth a dig before committing to more aggressive terrain. Forecasters are still tracking the Dec 8th layer (surface hoar, facets, crust) now down 40 to 80cm, but this layer has been inactive in recent days. The November rain crust is also worth keeping an eye on, as it has been responsible for a few recent large avalanches.

Terrain and Travel

  • Avoid areas where the snow feels stiff and/or slabby.
  • Avoid convexities, steep unsupported terrain and rocky outcroppings.
  • Avoid lee and cross-loaded terrain.
  • Be especially cautious as you transition into wind affected terrain.
  • Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs (now buried by up to 15cm of recent snow) are widespread. In steep and unsupported terrain, they could be sensitive to human triggering.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Recent avalanches have stepped down to this layer triggerring large avalanches. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3.5

Valid until: Dec 29th, 2020 3:00PM