Avalanche Forecast
Human-triggered persistent slabs remain a concern at treeline and above where no crust exists. Opt for low-consequence terrain away from overhead hazard to increase your safety margin.
Confidence
Moderate
Avalanche Summary
At treeline and above, a few wet loose avalanches were seen from steep terrain features. Where a thick, supportive surface crust is found, we expect that triggering avalanches on buried weak layers is unlikely.
Evidence from last week's natural avalanche cycle continued to be reported with very large slab avalanches (to size 4) failing on buried persistent weak layers.
Snowpack Summary
A melt-freeze crust has formed on most surfaces. Dry snow persists on northerly aspects at upper elevations.
Three persistent weak layers remain notable in the snowpack and have been responsible for recent large avalanches. Surface hoar that formed in mid-March can be found 50 to 100 cm below the snow surface. Below this, another layer of surface hoar that formed in early March can be found at a depth of 100 to 150 cm. Additionally, a layer of facets, surface hoar, and/or a crust from mid-February is buried 100 to 200 cm deep.
Weather Summary
Tuesday Night
Partly cloudy. 15 to 30 km/h northwest ridgetop wind. Treeline temperature -4 °C. Freezing level 800 m.
Wednesday
Mix of sun and cloud. 25 to 40 km/h northwest ridgetop wind. Treeline temperature -1 °C. Freezing level 1300 m.
Thursday
Mix of sun and cloud. 10 to 20 km/h west ridgetop wind. Treeline temperature +3 °C. Freezing level 1700 m.
Friday
Mostly cloudy. 20 to 40km/h southwest ridgetop wind. Treeline temperature +3 °C. Freezing level 1700 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be aware of the potential for large avalanches due to buried weak layers.
- Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
- Back off slopes as the surface becomes moist or wet with rising temperatures.
- Carefully manage your exposure to overhead hazards.
Avalanche Problems
Persistent Slabs
Surface hoar and facets in the upper snowpack have recently produced large avalanches. These layers are mostly likely to be reactive at upper elevations where no surface crust has formed.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 3.5
Cornices
As temperatures rise, large cornice falls will become a concern. They can potentially trigger persistent slab avalanches on the slopes below.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 2.5