Avalanche Forecast

Issued: Jan 9th, 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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Yesterday's storm slab is today's wind slab.

New snow, warming temperatures and increasing winds will promote slab formation. Use caution entering wind-affected terrain.

Summary

Confidence

Moderate - Uncertainty is due to difficult to forecast freezing levels.

Weather Forecast

A noticeable shift in the weather pattern, as warm temperatures embrace the region with light amounts of snowfall throughout the week.

Sunday Overnight: Partially cloudy. Strong to extreme southwest winds. A temperature inversion is possible, with temperatures in the alpine around 0 C.

Monday: Cloud cover increasing in the afternoon, light flurries. Strong to extreme southwest winds. Freezing levels around 1300m.

Tuesday: Snowing, 2-10 cm of accumulation. Strong southwest winds. Freezing levels around 1500m. 

Wednesday: Snowing, up to 5 cm accumulation. Moderate to strong southwest winds. Freezing levels around 1000m.

Avalanche Summary

If you are out in the mountains, let us know what you see by filling out a Mountain Information Network report! 

Snowpack Summary

Yesterday's storm brought up to 30 cm to areas in the south of the region, with tapering amounts to the north. Strong southwest winds will continue to redeposit this snow into wind slabs in lee areas in the alpine and treeline. 

This storm's 10-30 cm of new snow overlies 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 storm slabs.

A crust that was formed at treeline elevations and below in early December has been reported in parts of this region. It can be found down 50-100 cm. There have been no recent reports of avalanches on this layer. While the layer is now dormant in the region, a large amount of new snow or warming temperatures have the potential to wake it up, and wind slab avalanches may still have the potential to step down to this layer in isolated areas. 

The base of the snowpack is composed of crusts and weak faceted grains, particularly in thin snowpack areas east of the divide. 

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Avoid steep slopes when air temperatures are warm, or solar radiation is strong.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
  • Avoid exposure to slopes that have cornices overhead.

Problems

Wind Slabs

An icon showing Wind Slabs

Southwest winds will continue to redeposit new snow into wind slabs in lee areas in the alpine and treeline. Expect larger, and more reactive slabs in areas that received greater snowfall amounts in yesterday's storm. 

Rising temperatures throughout the day could rapidly increase the likelihood of natural and human-triggered avalanches. Watch for changing conditions, and if you see strong solar radiation, a rapid rise in temperatures or temperatures above 0 C, avoid steep slopes and overhead hazards.

Aspects: North, North East, East, South East, West, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Valid until: Jan 10th, 2022 4:00PM