Avalanche forecast

Purcells

Mar 3 – 4, 2022Avalanche Canada
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Avalanche danger

Sat
Sun
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

Stability is gradually improving but don't be too cavalier about decision making.

Test the bond of new snow on smaller features with low consequences before committing to bigger lines. 

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–2.5

    Human triggering of storm slabs should remain on your radar, especially in the southwestern part of the region where we have seen the greatest snowfall amounts. 

    Even in lower snowfall areas, don't discount recent moderate to strong southwest winds, loading lee slopes around ridge crests, as well as cross-loaded features. Cornices are likely growing as well. Investigate the bond of new snow carefully before committing to your line.

Confidence

Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.

Weather Forecast

Wednesday night: Light flurries, trace to 5 cm, light southwest wind, treeline low around -2.

Thursday: Overcast, trace to 5 cm, light southwest wind, treeline highs around zero. Freezing levels near valley bottom at night and rising to around 1600-1700 m during the day.

Friday: Light flurries easing in the morning, mix of sun and cloud light northeast wind, treeline highs around -2, freezing level around 1500 m.

Saturday: Mostly sunny, light northeast winds, treeline highs of -2.

Avalanche Summary

Evidence of a natural avalanche cycle in the size 2-2.5 range at all elevations has been observed in the southwest of the region. Some smaller natural soft slabs and skier-controlled wind slabs were also reported Wednesday. On Tuesday there was a remotely triggered size 2 storm slab avalanche in the west of the region, and some smaller wind and storm slabs reported elsewhere. On Monday in the northern Purcells there was a skier controlled size 1.5 wind slab on a north-facing cross-loaded feature. 

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 (10-45 cm) overlies 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.

Terrain and Travel

  • If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
  • Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
  • Use small low consequence slopes to test the bond of the new snow.

Regions covered