Bulletin d’avalanche

Banff Yoho Kootenay

Mar 26 – 27, 2026Avalanche Canada
Voir sur la carte
Archivé · expiré 6 months ago

Danger d’avalanche

Sat
Sun
Alpin
3 · Marqué
Limite forestière
2 · Modéré
Sous la limite
1 · Faible

Points saillants

New snow and wind has refreshed the ski quality but also made for reactive wind slabs in the immediate lees and storm slabs on the Mar 20 crust.

Be mindful of the luring effect of the sunny skies and powdery snow in the next few days.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–2

    20-50 cm of new snow with strong SW winds have formed reactive windslabs. The slabs are generally soft and predictable but extend further downslope due to the strong gusty winds.

    Below treeline, reactive storm slabs on the Mar 20 crust have also occurred in areas where we received more snow (KNP).

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    2–3.5

    A facet/surface hoar/crust interface from January is buried 70–180 cm deep. An extensive natural cycle occurred on this layer last week. We continue to see hard, sudden test results at elevations above the Mar 20 rain crust (~2300 m). Cornice falls / surface avalanches may trigger this layer.

  • Loose Dry

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    1–1.5

    15 - 40 cm of new snow will sluff easily in steep terrain and may be triggered by solar input or strong winds. This new snow sits on sun or hard rain crusts and may run faster and further than it otherwise would.

Confidence

Moderate

  • We are uncertain about how quickly persistent slabs are gaining strength.

Avalanche Summary

Lake Louise and Sunshine ski hill reported soft slabs in immediate alpine and treeline lees, generally 20 cm thick to a maximum of 60 cm deep. These were reactive with ski cuts and explosives at Louise and with every shot at Sunshine, but were failing predictably and not propagating too far.

Small storm snow avalanches failing on the March 20 rain crust were reported in Kootenay on Wednesday.

Snowpack Summary

15 - 40 cm of new snow fell this week with strong SW winds. This fell on the Mar 20th rain crust which exists below ~2300m. Above this crust, various sun crusts exist on solar aspects, extending to higher elevations.

The January 24th facet layer is buried 70–180 cm deep at treeline and in the alpine, with some tests still producing hard, sudden results.

Weather Summary

Friday - mostly sunny with moderate to strong SW wind that will continue to build windslabs and cornices. Treeline temperatures will be approximately -8C.

Saturday & Sunday - mix of sun and cloud, moderate SW wind, and treeline temperatures -5C

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
  • Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
  • Give the new snow several days to settle and stabilize before pushing into bigger terrain.

Régions couvertes