Avalanche forecast

Kootenay Boundary

Apr 1 – 2, 2024Avalanche Canada
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Avalanche danger

Wed
Thu
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable

Highlights

Rapidly rising freezing levels are expected to increase the likelihood of triggering large avalanches.

Choose conservative terrain and avoid overhead hazards.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–3.5

    Rapid warming increases the likelihood of triggering very large avalanches on deeply buried weak layers.

  • Storm Slabs

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

    Storm slabs continue to be reactive to human triggers, especially at treeline and above. They have been failing just above a crust down 30 to 50 cm.

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1–1.5

    Expect the high freezing levels to trigger wet loose avalanches on all aspects and elevations.

Confidence

High

Avalanche Summary

Numerous rider triggered storm slab avalanches up to size 1.5 were reported on primarily northerly aspects at treeline and above on Sunday. The Nelson area has been a hot spot for recent human triggered avalanches.

Numerous naturally triggered wet loose avalanches up to size 1.5 were also reported throughout the region.

Snowpack Summary

Strong solar radiation has formed a surface crust everywhere except north facing terrian at upper elevations.

30 to 50 cm of snow overlies a crust on all but north facing aspects at treeline and above where a weak layer of surface hoar may be present.

A persistent weak layer of facets are sitting on top of a second buried crust down 100 to 180 cm. This layer is unlikely to human trigger in areas where a thick crust below the recent snow is present. However, steep or convex terrain features with a shallow or thin to thick snowpack at treeline and above are the most likely places where it may be possible to trigger this layer with large loads.

Weather Summary

Monday Night

Clear skies. 10 to 20 km/h west ridgetop wind. Treeline temperature 6° C. Freezing level 2700 m.

Tuesday

Sunny. 20 to 30 km/h southwest ridgetop wind. Treeline temperature 8° C. Freezing level 2800 m.

Wednesday

Mix of sun and cloud with isolated flurries, 0 to 5 cm snow. 10 to 20 km/h west ridgetop wind. Treeline temperature -1° C. Freezing level 1800 m.

Thursday

Mix of sun and cloud. 10 to 20 km/h northeast ridgetop wind. Treeline temperature -2° C. Freezing level 1700 m.

Check out the Mountain Weather Forecast for additional weather information.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • The more the snowpack warms-up and weakens, the more conservative you`ll want to be with your terrain selection.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
  • If triggered loose wet avalanches may step down to deeper layers resulting in larger avalanches.
  • Cornice failure may trigger large avalanches.

Regions covered