Avalanche Forecast
Issued: Feb 21st, 2025 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
Avalanche Canada,
Avalanche Canada
As the storm slab problem worsens, the easy solution is to choose more conservative terrain.Stick to simple, low-angle slopes and avoid overhead hazards as remote-triggering is a concern.
Summary
Confidence
Low
Avalanche Summary
No recent slab avalanches have been reported, however, whumpfing which is a strong sign of unstable snow, was reported on Thursday. Check out the MIN report. Additionally, over the last few days, several small (size 1 to 1.5) natural and human-triggered dry loose avalanches were reported running in steep terrain.
Looking forward, we expect avalanche activity to rapidly increase as snow starts to accumulate along with strong winds and warming over the weekend.
Snowpack Summary
Overnight and through Saturday, 10 to 25 cm of fresh snow is expected, accompanied by moderate to strong southerly winds. This will contribute to widespread, sensitive storm slabs. This new snowfall will accumulate on top of 10 to 20 cm of existing snow, which currently rests on surface hoar from mid-February or a thin sun crust on steep, south-facing slopes. Beneath this, 20 to 60 cm of faceted snow sits atop a surface hoar layer buried in late January, which has been most reactive where a slab has developed above it. For more insight into slab formation, check out this blog. Outside of these layers, the remaining snowpack is generally well-settled.
Weather Summary
Friday Night
Cloudy with 5 to 15 cm of snow. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -4 °C.
Saturday
Cloudy with 5 to 15 cm of snow, possible rain below 1500 m. 30 to 40 km/h south ridgetop wind. Treeline temperature -2 °C. Freezing level rising to 1600 m.
Sunday
Mostly cloudy with 5 to 15 cm of snow, possible rain below 1600 m. 40 to 50 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 2000 m.
Monday
Partly cloudy with 0 to 2 cm of snow. 20 to 30 km/h southwest ridgetop wind. Treeline temperature -3 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid avalanche terrain during periods of heavy loading from new snow, wind, or rain.
- Approach steep and open slopes at and below treeline cautiously, as buried surface hoar may exist.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks, or recent avalanches.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Problems
Storm Slabs
Up to 25 cm of new snow is expected, combined with warming and strong winds. Storm slabs are expected to get more reactive throughout the day.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
A persistent weak layer buried 30 to 70 cm is expected to become more reactive as new snow overloads it.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 22nd, 2025 4:00PM
