Avalanche Forecast
Regions: Birkenhead, Duffey, South Chilcotin, South Coast Inland, Stein, Taseko.
Fresh wind slabs will develop with the new snow and wind.
The potential for a step-down avalanche remains with the persistent slab problem.
Confidence
Moderate
Avalanche Summary
On Monday, two very large persistent slabs were remotely triggered by skiers and a snowcat in the Birkenhead area. They occured on west and east alpine slopes and ran full path. Crowns were 75 to 100 cm and one of them stepped down to the mid-February week layer.
Debris from natural and human-triggered avalanches (such as cornice falls, wind, and storm slabs) from the stormy weekend continues to be reported in the region (up to size 3).
Snowpack Summary
Up to 10 cm of new snow and strong wind is expected by Thursday afternoon, forming small but touchy wind slabs. This overlies wind-affected snow in lee terrain at upper and a melt-freeze crust on southerly slopes up to 2000 m. This sits over 80 to 150 cm of settling storm snow from the past week.
The early March weak layer of facets or surface hoar on a crust is now down 100 to 150 cm and present on all aspects except high north-facing slopes. Very large avalanches (size 3 to 3.5) were reported on this layer in the past week.
Weak layers formed in mid-February and late-January are now buried 110 to 190 cm deep.
Weather Summary
Wednesday Night
Cloudy with up to 5 cm of new snow. 40 to 60 km/h south ridgetop wind. Treeline temperature -6 °C. Freezing level 800 m.
Thursday
Cloudy with up to 5 cm of new snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1200 m.
Friday
Cloudy with 10 to 20 cm of new snow with convective flurries. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1200 m.
Saturday
Cloudy with isolated flurries. 15 to 25 km/h west ridgetop wind. Treeline temperature -2 °C. Freezing level 1200 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be alert to conditions that change with elevation, aspect, and exposure to wind.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Cornice failures could trigger large and destructive avalanches.
- Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.
Avalanche Problems
Wind Slabs
New snow and wind will create fresh wind slabs. Use caution as you transfer into wind-affected terrain, as these slabs may be reactive to riders.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 1.5
Persistent Slabs
Weak layers remain a concern in north-facing terrain where snowpack depth is variable. There's still uncertainty about avalanches stepping down to these layers, potentially triggering very large avalanches.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1.5 - 3