Avalanche Forecast
Regions: Birkenhead, Duffey, South Chilcotin, South Coast Inland, Stein, Taseko.
Dangerous avalanche conditions exist. Careful snowpack evaluation, cautious route-finding, and conservative decision-making are essential.
Confidence
Moderate
Avalanche Summary
On Friday, explosive control in the region produced four size 2.5 persistent slab avalanches on northwest alpine features. A few dry loose avalanches were also observed up to size 1.5.
On Monday, two very large persistent slabs were remotely triggered by skiers and a snowcat in the Birkenhead area. They occurred 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.
Snowpack Summary
15 to 30 cm of new snow and southwest winds reactive wind slabs on lee slopes at higher elevations. New snow overlies wind-affected snow at upper elevations 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 is 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
Friday Night
Partly cloudy. 10 to 25 km/h southwest ridgetop wind. Treeline temperature -8 °C. Freezing level drops to valley bottom.
Saturday
Mix of sun and clouds. 15 to 25 km/h southwest ridgetop wind. Treeline temperature -5 °C. Freezing level 1200 m.
Sunday
Mostly cloudy with isolated flurries, 2 cm of snow. 30 to 40 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 1600 m.
Monday
Mix of sun and clouds. 20 to 30 km/h southwest ridgetop wind. Treeline temperature +2 °C. Freezing level 2000 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
- Even brief periods of direct sun could produce natural avalanches.
- Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
Avalanche Problems
Wind Slabs
New snow and southwest wind have created fresh wind slabs, which will likely be more reactive in leeward terrain and around ridge crests. If triggered, a wind slab may step-down to deeper layers resulting in large avalanches.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Persistent Slabs
Weak layers remain a concern, especially in north-facing terrain where snowpack depth is variable. Avoid steep and shallow rocky features where human triggering is possible.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1.5 - 3
