Avalanche Forecast
Regions: Birkenhead, Duffey, South Chilcotin, South Coast Inland, Stein, Taseko.
During periods of high hazard, avoid all avalanche terrain.
We expect a large natural avalanche cycle with snow, strong winds, and buried weak layers.
Confidence
Moderate
Avalanche Summary
On Friday, skiers remotely triggered this very large avalanche near Vantage Peak. Explosive control in the region produced four size 2.5 persistent slab avalanches on northwest alpine features.
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
Up to 25 cm of new snow is expected, and will be redistributed into deeper and more reactive deposits on north- and east-facing slopes by strong to extreme southwesterly winds. This overlies 15 to 30 cm of recent snow and then 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 old snow.
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 this past week.
Weak layers formed in mid-February and late-January are now buried 110 to 190 cm deep.
Weather Summary
Saturday Night
Cloudy with up to 10 cm of snow. 30 to 60 km/h southwest ridgetop winds. Treeline temperature -9 °C.
Sunday
Cloudy with up to 15 cm of snow. 30 to 40 km/h southwest ridgetop winds. Treeline temperature -3 °C. Freezing level rises to 1500 m by 4 pm.
Monday
Cloudy with 5 to 10 mm, falling as snow above 1500 m. 20 to 40 km/h southwest ridgetop winds. Treeline temperature 2 °C.
Tuesday
Cloudy with up to 5mm, falling as snow above 2000 m. 50 km/h southwest ridgetop winds. Treeline temperature 4 °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.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
- Only the most simple non-avalanche terrain with no overhead hazard is appropriate at this time.
Avalanche Problems
Storm Slabs
Storm snow and strong southwest winds will form touchy storm slabs. Expect to find deeper and more reactive deposits on north- and east-facing slopes.
Storm slabs may step-down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Very Likely
Expected Size: 1.5 - 2.5
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 - 3.5