Bulletin d’avalanche

Lizard-Flathead

Apr 3 – 4, 2021Avalanche Canada
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Archivé · expiré 5 years ago

Danger d’avalanche

Mon
Tue
Alpin
2 · Modéré
Limite forestière
1 · Faible
Sous la limite
1 · Faible

Points saillants

Convective flurries on Sunday and southwesterly winds may form small wind slabs sitting on slippery crusts below alpine ridgetops. Use caution when transitioning into wind affected terrain.

Problèmes avalancheux

  • Wind Slabs

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

    Convective flurries on Sunday and southwesterly winds may form small wind slabs sitting on slippery crusts on lee features below alpine ridgetops.

  • Cornices

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Possible
    Taille
    1.5–2.5

    Cornices are large and looming along many ridgelines. They are capable of triggering large avalanches when they fail.

Confidence

High -

Weather Forecast

  

SATURDAY NIGHT: Clear skies / Moderate, southwest ridgetop wind / alpine low temperature -5 / Freezing level 2000 m.

SUNDAY: Snow flurries/rain; 5-15 cm. / Moderate, southwest ridgetop wind / alpine high temperature 2 / Freezing level 1700 m.

MONDAY: Sunny / Light, southeast ridgetop wind / alpine high temperature 6 / Freezing level 2200 m.

TUESDAY: Sunny / Light, west ridgetop wind / alpine high temperature 8 / Freezing level 2500 m.

Avalanche Summary

On Friday, naturally triggered wet loose avalanches up to size 1.5 were reported on steep solar aspects in the alpine.

Snowpack Summary

Convective flurries on Sunday and southwesterly winds may form small wind slabs sitting on slippery crusts on lee features below alpine ridgetops. Crusty surfaces exist on all but north facing terrain at upper elevations.

Cornices are large, looming, and capable of triggering large avalanches when they fail.

The mid-pack is firm and well settled. Some faceted snow and a decomposing melt-freeze crust can be found near the base of the snowpack. 

 Glide cracks releasing as full depth glide slab avalanches become more common in the spring and are extremely difficult to predict. Best practice is to avoid slopes with glide cracks.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Wind slabs may be poorly bonded to the underlying crust.
  • Be alert to conditions that change with elevation and sun exposure.
  • Avoid exposure to slopes that have cornices overhead.

Régions couvertes