Avalanche Forecast

Issued: Jan 11th, 2022 4:00PM

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

Avalanche Canada cgarritty, Avalanche Canada

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New snow and wind will keep our wind slab problem alive for Wednesday. Meanwhile, the snowpack will be adjusting to warming temperatures. The effects of this warming are uncertain so it's a good time to build extra safety margins into your terrain selection.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain.

Weather Forecast

Tuesday night: Cloudy with flurries bringing about 5 cm of new snow. Moderate southwest winds.

Wednesday: Mainly cloudy with isolated flurries, increasing overnight. Light to moderate southwest winds. Treeline high temperatures around -3 with freezing levels to 1400 metres.

Thursday: Mainly cloudy with lingering flurries from overnight and 10-20 cm of new snow. Light southwest winds shifting northwest. Treeline high temperatures around -2, cooling over the day as freezing levels fall from 1400 metres.

Friday: A mix of sun and cloud. Light south winds becoming strong by evening. Treeline high temperatures around - 2 with freezing levels rising to 1300 metres.

Avalanche Summary

Reports from Monday included a few small (size 1) new ski cut wind slabs. This potential should increase a notch for Wednesday as new snow, wind, and warming make their way into the region.

On Sunday, numerous small, loose dry avalanches were reported on slopes that saw the sun.

On Saturday, small, isolated, rider-triggered windslab avalanches were reported at treeline, along with a single, larger, naturally triggered windslab avalanche in the alpine.

There are very few reporting operations in this region, so remember that a lack of observed avalanches does not necessarily mean that there is a lack of avalanche activity. If you are getting out, please share your observations on the Mountain Information Network!

Snowpack Summary

Up to 15 cm of new snow is expected by Wednesday morning, adding to generally wind-effected surfaces in the alpine and in exposed terrain around treeline. In sheltered areas, it add to up to 50 cm of low density snow that is starting to settle and get denser as temperatures rise.

Our new snow, recent windslabs, and settling snow are sitting on top of faceted snow that formed during the colder weather last week. Forecast new snow and warming mean these upper snowpack layers may become increasingly upside-down and more likely to avalanche. 

There have been isolated reports of two buried surface hoar layers between 25 and 80 cm deep in the Barkerville area. Due to few recent observations in this area, it's wise to assume that these layers remain in play and still have the potential to fail under the weight of a rider. Forecast new snow and warming should again add to this potential.

This recent Mountain Information Network (MIN) post has a great summary of conditions around the Mt Murray cabin, and some snowpack observations that may relate to one of these surface hoar layers.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
  • Be alert to conditions that change with aspect and elevation.

Problems

Wind Slabs

An icon showing Wind Slabs

Light new snow amounts feeding into southwest winds will continue to deposit new snow into wind slabs in lee areas in the alpine and treeline as well as in exposed areas below treeline. A pattern of rising temperatures will promote slab formation and slab reactivity on Wednesday.

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

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Jan 12th, 2022 4:00PM