Avalanche forecast

Banff Yoho Kootenay

Dec 6 – 7, 2023Avalanche Canada
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Avalanche danger

Fri
Sat
Alpine
4 · High
Treeline
3 · Considerable
Below
2 · Moderate

Highlights

An avalanche cycle is happening with heavy wet storm snow overlaying a generally weak faceted snowpack. Skiers should be choosing conservative terrain. Ice-climbers should be picking routes with no over-head hazard.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely - Certain
    Size
    1–2

    Up to 35cm of heavy wet storm snow is sitting on a weak faceted snowpack and may become more reactive as it settles.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely - Certain
    Size
    1–2

    The mid and lower pack are thin and faceted in most areas. Surface avalanches could scrub down to the facets resulting in a full depth avalanches.

Confidence

Moderate

Avalanche Summary

Numerous natural avalanches up to size 2 were reported on Tuesday running as storm slabs and deep persistent slabs at all elevations. Widespread whumphing and cracking was reported in areas not steep enough to avalanche.

Snowpack Summary

Up to 35 cm of moist storm snow overlays well developed surface hoar, faceted snow, and sun-crusts on steep south aspects. Previous strong SW winds have formed windslabs in alpine and tree-line locations. The mid and lower pack is generally weak and faceted. Snow depths range from 40-60 cm at tree-line and up to 90 cm in deeper alpine locations.

Weather Summary

A continued SW flow will bring more snow to the forecast area on Wednesday with another 20 cm possible by the evening. Freezing levels will hover around 1300m then lower to valley bottom on Thursday. Winds should taper through the day on Wednesday and switch from SW to W.

For more information click Mountain Weather Forecast.

Terrain and Travel Advice

  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.
  • Avoid exposure to overhead avalanche terrain, avalanches may run surprisingly far.

Regions covered