Avalanche forecast

Kootenay Boundary

Mar 13 – 14, 2024Avalanche Canada
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Avalanche danger

Fri
Sat
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable

Highlights

Stick to mellow terrain, and avoid travelling in or under large, open slopes.

Rider or sun-triggered avalanches could become very large if they step down to a deeper weak layer.

Avalanche problems

  • Persistent Slabs

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

    While uncertainty exists about the likelihood of triggering, storm snow will add load and may increase reactivity. Avoid areas where the snowpack thins, like steep, rocky start zones where weak layers are more easily triggered.

  • Storm Slabs

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

    Storm snow is not bonding well with the old snow surface. Human triggered avalanches are likely. Use extra caution around ridgecrests, rolls, and on convex slopes.

  • Loose Wet

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

    With lots of recent storm snow, and intense spring sun in the forecast, loose avalanches are likely.

Confidence

Moderate

Avalanche Summary

On Monday and Tuesday, several small to large (up to size 2.5) natural and rider triggered wind and storm slab avalanches were reported at treeline and below.

Limited persistent slab activity has been reported since Thursday, however, avalanches within the last week have been large and destructive, running full path.

See photos below for examples.

Snowpack Summary

40-60 cm of recent snow is currently not bonding well with the old snow surface - a crust on sun affected slopes, surface hoar in sheltered terrain, and wind affected snow in exposed areas. With sunny skies and rising freezing levels, expect to see more moist or wet snow on the surface as the day goes on.

A widespread crust with weak facets above is buried 120-160 cm deep and remains a very concerning layer for human triggering. While reports suggest this layer is becoming harder to trigger, it still warrants careful terrain choice.

The snowpack below the crust is generally strong.

Weather Summary

Wednesday Night

Clear. No new snow expected. Light northwest ridgetop wind. Freezing level falls to 1400 m, with treeline temperatures around -3 °C.

Thursday

Sunny. No new snow expected. Light northwest ridgetop wind. Freezing levels rise to 2000 m, with treeline high around 0 °C.

Friday

Sunny. No new snow expected. Light to moderate northwest ridgetop wind. Freezing levels rise to 3100 m, with treeline high around 5 °C.

Saturday

Sunny. No new snow expected. Light southeast ridgetop wind. Freezing level around 3100 m, with treeline high around 7 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.
  • Avoid avalanche terrain during periods of strong sun.
  • Be mindful that deep instabilities are still present and have produced recent large avalanches.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

Regions covered