Avalanche forecast

Banff Yoho Kootenay

Mar 25 – 26, 2023Avalanche Canada
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Avalanche danger

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

Highlights

Unstable air has brought convective flurries to the forecasting region over the last couple of days.

Expect bouts of both cloudy skies with intense snowfall and poor visibility, as well as sunny skies that can yield moist snow very quickly.

Human triggering of the persistent and deep persistent layers remains the main concern.

Avalanche problems

  • Persistent Slabs

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

    Three persistent weak layers formed in January are down 40-110 cm. The buried sun crusts on steep solar slopes that have been the greatest concern for triggering are now covered by surface crusts making triggering in these locations less likely. Meanwhile the weak facets that can be found on these same interfaces on shaded aspects remain a concern.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–4

    The weak depth hoar at the bottom of the snowpack inspires little confidence. Give careful consideration to the slopes overhead as large avalanches may run well into the runout zone or into lower-angle terrain. Avoid big terrain features and be especially cautious in thin or rocky areas, where triggering is more likely.

Confidence

Moderate

Avalanche Summary

No new avalanches were observed or reported Saturday.

Snowpack Summary

5-15 cm of snow fell March 24 to bury temperature crusts to 1600m, sun crusts to ridgetop on solar aspects and facets on shaded slopes.

The middle of the snowpack holds several crust and facet layers.

The base of the snowpack is weak, unconsolidated depth hoar in almost all areas.

Cornice failures occur regularly at this point of the season.

Weather Summary

Cloudy skies will start to clear into Sunday morning with the potential for a few flurries giving way to the potential for sunshine in the afternoon. Cloud will re-build overnight Sunday, again with the potential for flurries. Freezing levels will reach 1500m Sunday with further cooling for Monday. Alpine winds will remain light Sunday but may just touch into moderate on Monday.

Terrain and Travel Advice

  • Uncertainty is best managed through conservative terrain choices at this time.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Regions covered