Avalanche Forecast
Regions: Dogtooth, East Purcell, Purcells.
Don't let your guard down as snowfall begins. Buried weak layers remain likely to trigger.
Avoid exposing yourself to large slopes or avalanche paths.
Confidence
Moderate
Avalanche Summary
Over the last 3 days natural avalanche activity appears to be decreasing, but human triggering continues. Slabs have been triggered by riders including remote triggers from up to 100 m away, indicating weak layers remain sensitive.
Persistent slab avalanches have been reported to size 3.5 this week. If triggered a large and destructive avalanche remains likely as shown by this remotely triggered avalanche near Golden on Thursday.
Snowpack Summary
Light accumulations of storm snow will fall over sun crusts on south facing slopes, lightly wind-affected snow at higher elevations, and settling snow elsewhere.
A widespread crust is roughly 80-120 cm deep. Weak faceted crystals and surface hoar above this crust are contributing to large avalanches across the province and continue to be the primary layer of concern here.
Additionally, the lower snowpack is mostly made up of weak and faceted layers.
Weather Summary
Sunday Night
Mostly cloudy with 5-15 cm of snow. 20-40 km/h southwest ridgetop wind. Freezing levels drop to 1000 m.
Monday
Mostly cloudy with possible flurries. 20-30 km/h southwest ridgetop wind. Freezing levels rise to 1700 m by the afternoon. Treeline temperature -3 °C.
Tuesday
Mostly cloudy. 10-20 km/h southwest ridgetop wind. Freezing levels rise to 1800 m. Treeline temperature -2 °C.
Wednesday
A mix of sun and cloud 10-20 km/h northwest ridgetop wind. Freezing levels rise to 1700 m Treeline temperature -3 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Conservative terrain selection is critical, choose only well supported, low consequence lines.
- Remote triggering is a concern, watch out for adjacent and overhead slopes.
- Be aware of the potential for large, destructive avalanches due to the presence of deeply buried weak layers.
Avalanche Problems
Persistent Slabs
Avoid areas where the snowpack thins, like steep, rocky start zones at treeline and alpine elevations. Weak layers are more easily triggered here.
Stick to simple terrain features to minimize exposure to this problem.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 2 - 3.5
Wind Slabs
Reactive wind slabs likely exist on north and east facing slopes around ridgelines. Small wind slabs could step down to deeper weak layers producing very large avalanches.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 2