Avalanche Forecast
Another warm-up brings rising avalanche risk. Read the new forecasters' blog.
Uncertainty is due to how buried persistent weak layers will react to the upcoming warm weather.
Confidence
Moderate
Avalanche Summary
On Monday, 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
Thursday Night
Mainly clear. 10 to 20 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 1400 m.
Friday
Mix of sun and cloud. 30 to 40 km/h southwest ridgetop wind. Treeline temperature +6 °C. Freezing level 2000 m.
Saturday
Mix of sun and cloud. 40 to 60 km/h south ridgetop wind. Treeline temperature +4 °C. Freezing level 2000 m.
Sunday
Mostly cloudy with 5 to 10 cm of new snow. 30 to 40 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 1400 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.
- 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.
Avalanche Problems
Persistent Slabs
Weak layers of surface hoar and facets in the upper snowpack have recently produced large avalanches. Surface instabilities or large triggers may step down to these deeper layers.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 2 - 3.5
Cornices
As temperatures rise, large cornice falls will become a concern. They can potentially trigger persistent slabs on the slopes below. Carefully manage your exposure to overhead hazards, during the warmest part of the day.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible - Likely
Expected Size: 1 - 2.5