Avalanche forecast

Purcells

Feb 2 – 3, 2023Avalanche Canada
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Avalanche danger

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

Continue to exercise patience with this snowpack and avoid aggressive terrain choices.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–1.5

    Wind slabs can be found at all elevations in open terrain features and range from soft to hard slabs depending on exposure to recent winds.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–2.5

    Several weak layers sit in the upper and mid snowpack at prime depths for human triggering. Avoid convex rolls in sheltered terrain where buried surface hoar may be present. Stay disciplined and choose well supported, low consequence lines.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2.5–4

    A weak layer near the base of the snowpack, buried in November, continues to be reactive. Human and natural triggering of this layer remain possible, especially in shallow areas with variable snow depths. Avoid thin and rocky start zones and select routes that avoid exposure to large avalanche paths.

Confidence

Moderate

Avalanche Summary

Small wind slabs continue to be triggered both naturally and with explosive control work, most of these occurrences were in the western part of our region.

Over the weekend a very large natural size 4 deep persistent slab avalanche was reported. This avalanche started as a wind slab in steep rocky terrain and stepped down to the ground.

Snowpack Summary

Wind slabs up to 20 cm in depth can be found on a variety of surfaces including previously wind-affected snow, a small layer of surface hoar, and a sun crust.

Our mid-pack has two layers that remain of concern. The first is down 20 to 40 cm and is a layer of surface hoar from early January. The second, is a layer of surface hoar, facets, and crust down 40 to 60 cm.

A layer from late November is down 70 to 130 cm and is part of a generally weak faceted snowpack. Snowpack depths range between 80 and 180 cm at treeline and are shallowest in the eastern part of our region.

Weather Summary

Wednesday Night

Partly cloudy, flurries 2 to 3 cm of new snow, winds 15 to 20 km/h westerly, treeline temperatures of -8 °C.

Thursday

Mostly clear skies, trace accumulations in the morning, 15 to 20 km/h southwest winds. Treeline temperatures -4 °C.

Friday

Increasing clouds, 2 to 5 cm of new snow starting later in the day, 10 to 20 km/h southwest winds, treeline temperatures -5 °C.

Saturday

Mostly cloudy, 2 to 5 cm new snow, 15 to 20 km/h southwest winds, treeline temperatures -2 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
  • Uncertainty is best managed through conservative terrain choices at this time.
  • Approach lee and cross-loaded slopes with caution.

Regions covered