Avalanche forecast

Purcells

Jan 18 – 19, 2025Avalanche Canada
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Avalanche danger

Mon
Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low

Highlights

Wind slabs continue to be observed in the region.

Use extra caution in wind-affected terrain and continue to avoid steep, rocky slopes with shallow snow cover.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Recent winds have varied in direction, use caution when entering any wind-affected terrain. These slabs are expected to be most reactive where they overlie facets, surface hoar or a melt-freeze crust.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    1.5–3

    The early December weak layer remains a concern in areas with a shallow snowpack, particularly on steep rocky slopes.

Confidence

Moderate

Avalanche Summary

On Thursday, several size 1-2 wind slab avalanches were reported across the Eastern Purcells.

On Monday several human-triggered and natural avalanches were reported in the Jumbo area west of Invermere.

Looking to the weekend, we suspect wind slabs to remain possible to trigger, especially where they overlie a layer of surface hoar.

Snowpack Summary

A thin layer of recent snow has covered a variety of surfaces, including sun crust, surface hoar, and wind-affected snow. Recent winds have varied in direction, forming wind slabs on lee slopes.

Older wind slabs may still be found near ridgetops covering a 20 to 30 cm deep surface hoar layer from early January. These slabs may remain sensitive for an extended period.

A weak layer of facets buried in early December is on average 60 to 90 cm deep. In the shallower eastern parts of the Purcells, this layer may only be 30 cm deep. This layer continues to cause sporadic large avalanches.

The snowpack base consists of a thick crust and facets in many areas.

Weather Summary

Friday Night

Partly cloudy. 15 to 30 km/h northwest ridgetop wind. Treeline temperature -16 °C.

Saturday

Mostly sunny. 5 to 15 km/h variable ridgetop wind. Treeline temperature -20 °C.

Sunday

Mostly sunny. 15 to 20 km/h north ridgetop wind. Treeline temperature -21 °C.

Monday

Sunny. 10 km/h west ridgetop wind. Treeline temperature -18 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
  • Pay attention to isolated wind affected features in the alpine, as well as cross-loaded features at treeline.
  • Be aware of the potential for large avalanches due to buried weak layers.

Regions covered