Avalanche Forecast
Regions: Birkenhead, Duffey, South Chilcotin, South Coast Inland, Stein, Taseko.
Reactive wind slabs will build through the day on north through east aspects at upper elevations. If triggered, they could step down to persistent weak layers deeper in the snowpack.
Confidence
Moderate
Avalanche Summary
No new reports on Tuesday. We saw a social media post and on Drive BC that the Duffy road was closed from Tuesday afternoon through Wednesday due to an avalanche hitting the road. No further information to note.
With temperatures falling, natural avalanche activity may taper but human triggered avalanches remain likely, especially at upper elevations affected by forecasted new snow and wind.
Snowpack Summary
Rain and warming to mountaintop has saturated the upper snowpack from 30 to 40 cm deep on all aspects and elevations, except high north-facing alpine slopes. As freezing levels fall on Thursday, a widespread crust will form. New snow accompanied by strong south wind will likely build storm slabs at upper elevations. Expect deeper and more reactive deposits on north through east-facing slopes.
The early March weak layer of facets, or surface hoar on a crust is now down 80 to 170 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 180 to 250 cm deep.
Weather Summary
Wednesday Night
Cloudy with light rain 5 to 10 mm. 15 to 35 km/h south ridgetop winds. Treeline temperature 2 °C. Freezing level dropping to 1700 m.
Thursday
Mostly cloudy with some sun and flurries 5 to 10 cm. 20 gusting to 35 km/h southeast ridgetop winds. Treeline temperature -1 °C. Freezing level 1800 m.
Friday
Mostly cloudy with snow 10 to 15 cm above 1200 m. 15 to 35 km/h southeast ridgetop winds. Treeline temperature -2 °C. Freezing level 1500 m.
Saturday
Cloudy with scattered flurries up to 5 cm. 15 to 30 km/h southwest ridgetop winds. Treeline temperature -3 °C. Freezing level 1200 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Wind slabs are most reactive during their formation.
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
- Be especially cautious as you transition into wind-affected terrain.
Avalanche Problems
Wind Slabs
New snow accompanied by strong south winds will build fresh and reactive wind slabs on lee slopes at treeline and above.
Wet loose avalanches are possible where precipitation falls as rain at lower elevations.
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 - Likely
Expected Size: 1.5 - 3