Avalanche forecast

Banff Yoho Kootenay

Nov 28 – 29, 2022Avalanche Canada
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Avalanche danger

Wed
Thu
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Uncertainty remains with how the new snow will contribute to the likelihood of triggering persistent slabs, that were already overlying a weak base.

Avalanche problems

  • Wind Slabs

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

    Up to 20cm of new snow distributed by strong winds has created thin soft slabs. Many of these sit on older wind pressed surfaces.

  • Persistent Slabs

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

    Slabs overly weak facets (and even some depth hoar) in most areas, as well as suncrusts and surface hoar in isolated locations.

  • Loose Dry

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

    New snow and wind input on Sunday will promote loose dry avalanches. This is mainly a problem for ice climbers and skiers in steep, gullied terrain.

Confidence

Moderate

Avalanche Summary

Lake Louise ski area triggered a size 1.5 wind slab with explosives in a high alpine lee pocket. Otherwise no avalanches were observed or reported.

Snowpack Summary

Up to 20cm of new snow has accumulated in the last 3 days, less so in valley bottoms. Windy conditions has promoted wind slab development in the alpine. The snowpack below these slabs is a mix of facets, spotty surface hoar, and sun crust on steep south aspects. 40-80 cm of total snow exists at treeline throughout the region, with up to 120 cm in loaded alpine features.

Weather Summary

Dropping temperatures and clearing skies into Monday. -20 at the ridge and -15 in valley are expected. The wind will also decrease into the light range from the North.

https://avalanche.ca/weather/forecast

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.

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