Avalanche Forecast

Issued: Jan 7th, 2022 4:00PM

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

Avalanche Canada zryan, Avalanche Canada

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Avalanche danger will rise through the day as new snow and wind form fresh, reactive slabs.

Summary

Confidence

Moderate - Forecast precipitation (either snow or rain) amounts are uncertain. Uncertainty is due to the extreme variability of wind effect on the snowpack.

Weather Forecast

Friday Overnight: Light snowfall, up to 5 cm accumulation. Moderate to strong southwest winds. Alpine temperatures around -20 C.

Saturday: Snowing, 5-10 cm of accumulation. Strong southwest winds. Alpine temperatures rising to -15 C. Continued overnight snowfall, 10-15 cm accumulation.

Sunday: Snowfall easing, up to 5 cm accumulation. Strong southwest winds. Alpine temperatures around -15 C.

Monday: Light snowfall, 5 cm accumulation. Strong southwest winds. Alpine temperatures rising to -10 C.

Avalanche Summary

On Wednesday, explosives triggered a size 2 wind slab in the far south of the region. There has been evidence of a few natural wind slabs in the region which occurred at the beginning of the week. 

Observations have been limited due to the cold conditions. If you are out in the mountains, let us know what you see by filling out a Mountain Information Network report!

Snowpack Summary

Snowfall and southwest winds may build fresh wind slabs in lees the alpine and treeline throughout the day.

These fresh wind slabs overlie a previously wind affected surface comprised of old hard wind slabs, sastrugi, and areas stripped back to the ground or old crusts. Near surface faceting above the old surface may increase the reactivity of newly formed wind slabs.

The base of the snowpack is composed of crusts and weak faceted grains, particularly in thin snowpack areas. While these layers have generally gone dormant in the region, they still have the possibility of waking up with new snow load or warming, and wind slab avalanches may still have the potential to step down to these deeper layers in isolated areas. 

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Be aware of highly variable recent wind loading patterns.
  • The best and safest riding will be on slopes that have soft snow without any slab properties.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Avalanche danger will increase throughout the day as snowfall and southwest winds build fresh, reactive wind slabs in lee areas in the alpine and treeline.

Older, hard windslabs exists below the new snow from northeasterly outflow winds earlier in the week. These slabs may be quite stubborn to trigger, but would be larger and more consequential. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Jan 8th, 2022 4:00PM