Avalanche forecast

Purcells

Mar 1 – 2, 2022Avalanche Canada
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Avalanche danger

Thu
Fri
Alpine
4 · High
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

The southwestern side of the Purcells has seen the greatest snowfall amounts and will require more conservative terrain choices as new snow, moderate to strong southwest winds and rising freezing levels have combined to create dangerous avalanche conditions.

Avoiding travel in the alpine and sticking to conservative low-angle terrain is recommended.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely - Very Likely
    Size
    1–3

    Continued loading from new snow has formed storm slabs on all aspects. As the snow stacks up, storm slab size and sensitivity to triggering has increased. This is especially true in the southwest part of the region where we have seen the greatest snowfall amounts.

    Even in lower snowfall areas, don't discount the moderate to strong southwest winds, loading lee slopes around ridge crests, as well as cross-loaded features. Sticking to sheltered lower angle terrain out of the alpine is a good bet.

Confidence

Moderate - Recent weather patterns have resulted in a high degree of snowpack variability within the region.

Weather Forecast

Snowfall amounts vary by forecast model and location in the region. The southwest Purcells are expected to receive the most snow.

Monday Night: Snow 5-20 cm possible, strong southwest wind, low of -3 °C.

Tuesday: Snowfall 5-20 cm, moderate to strong southwest wind, freezing levels between 1700- 2000 m, treeline high of +2. 

Tuesday night into Wednesday: Light flurries, 3-8 cm, light to moderate southwest wind, treeline high around +2.

Wednesday night into Thursday: 5-10 cm, light southwest wind, treeline highs around +2.

Avalanche Summary

On Sunday and Monday there were reports of small (size 1-1.5) skier controlled wind slabs in in the region.

Snowpack Summary

Snowfall amounts have varied substantially throughout the region with the southwest side of the Purcells getting the greatest snowfall amounts. Recent storm snow (10-40 cm) will need time to bond to a variety of old surfaces such as firm wind-pressed snow, sun crust on solar aspects, surface hoar, and potential cold weak crystals on shaded aspects.

An interface from mid-February is likely now down 40-60 cm. This layer was previously only reactive in wind-loaded terrain where a slab had formed but may become more problematic if covered with a more widespread cohesive slab.

Below that on sheltered north aspects, there is still a surface hoar layer being tracked that was formed in late January. Though there haven't been reports of recent avalanches on this layer in this region, it is still on the radar of many operations and could potentially wake up during the storm. 

Terrain and Travel

  • As the storm slab problem gets trickier, the easy solution is to choose more conservative terrain.
  • Dial back your terrain choices if you are seeing more than 25cm of new snow.
  • Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
  • Stick to well supported, lower angle terrain.

Regions covered