Avalanche Forecast
Be patient, choose mellow terrain, and give the snowpack time to adjust to the new load.
Storm slabs and buried weak layers may be primed for human triggering.
Confidence
Moderate
Avalanche Summary
No new avalanches were reported on Saturday before 4 pm. We expect that human triggered avalanches will remain likely on Sunday.
If you go out in the backcountry, please consider sharing your observations on the Mountain Information Network (MIN).
Snowpack Summary
Friday night, 20-30 cm of storm snow arrived with strong southwest winds forming reactive storm slabs. This recent snow sits on old, hard surfaces, like windslabs or a frozen crust, which are good sliding surfaces for avalanches.
A concerning layer of surface hoar can be found 50-90 cm below the snow surface.
A crust with sugary facets beneath it can be found just above the ground. Average snowpack depths at treeline range from 65 to 100 cm.
Weather Summary
Saturday Night
Partly cloudy. Trace of snow expected. Light to moderate southwest ridgetop wind. Treeline low around -6°C. Freezing level at valley bottom.
Sunday
Partly cloudy. No new snow expected. Moderate southwest ridgetop wind. Treeline high around -2°C with possible temperature inversion.
Monday
Cloudy. 5-10 cm of snow expected. Light southeast ridgetop wind. Treeline temperature around -2°C with possible temperature inversion.
Tuesday
Cloudy. 2-5 cm of snow expected. Light to moderate southwest ridgetop wind. Treeline temperature around -2°C with possible temperature inversion.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- Give the new snow several days to settle and stabilize before pushing into bigger terrain.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Avalanche Problems
Storm Slabs
Recent snow and wind formed reactive slabs at all elevations. Use extra caution around ridgecrests, rolls, and on convex slopes. Retreat to mellower terrain if you find signs of instability like shooting cracks, or recent avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1.5 - 2.5
Persistent Slabs
Buried surface hoar remains concerningly reactive in snowpack tests. It is difficult to define the specific terrain where you could trigger this layer, due to a lack of snowpack and avalanche observations.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1.5 - 2.5