Bulletin d’avalanche

Yukon

Avalanche Canada
Voir sur la carte

Danger d’avalanche

Tue
Wed
Alpin
2 · Modéré
Limite forestière
1 · Faible
Sous la limite
Sans niveau
Open full map
Périmé — ce bulletin a expiré 4 months ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

Use extra caution in north-facing terrain at higher elevations, where wind slabs may be surprisingly reactive due to an underlying surface hoar layer.

Problèmes avalancheux

  • Wind Slabs

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

    Reactive wind slabs persist in steep northerly terrain and may be remotely triggered due to the underlying surface hoar layer.

  • Deep Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Unlikely
    Taille
    2–3

    A faceted lower snowpack presents a persistent slab problem. Weak layers deep in the snowpack may be triggered by cornice fall or on steep features where the snowpack transitions from thick to thin.

Confidence

Moderate

  • We are uncertain due to a limited number of field observations.

Avalanche Summary

A remotely triggered wind slab avalanche was skier-triggered on Friday on a north-facing slope at approximately 1900 m. The slab failed on the surface hoar layer mentioned in the snowpack summary, buried about 50 cm below the surface.

A second avalanche with very similar characteristics was reported just outside the forecast region in an area with a comparable snowpack.

Snowpack Summary

A variety of surfaces exist across aspects and elevations. Firm, supportive crusts are present at lower elevations and on sun-exposed slopes; these may soften with possible sunny breaks.

In higher-elevation terrain sheltered from sun and wind, a dusting of wind-affected new snow adds to roughly 15 cm of recent snow that overlies a mix of older, wind-affected surfaces.

A weak layer of surface hoar persists 40 to 70 cm below the surface in northerly alpine terrain.

The lower snowpack remains faceted and generally weak, especially in shallow snowpack areas.

Weather Summary

Sunday Night
Partly cloudy. 1 to 4 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -4 °C.

Monday
Mix of sun and clouds. 1 cm of snow. 20 km/h southwest ridgetop wind. Treeline temperature -5 °C.

Tuesday
Mix of sun and clouds. 4 to 5 cm of snow. 20 km/h northwest ridgetop wind. Treeline temperature -5 °C.

Wednesday
Mostly sunny. 1 cm of snow. 20 km/h southwest ridgetop wind. Treeline temperature -5 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
  • Be aware of the potential for remote triggering and large avalanches due to buried surface hoar.
  • Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.

Régions couvertes