Avalanche Forecast
Regions: Dogtooth, East Purcell, Purcells, West Purcell.
Wind slabs continue to be observed in the region.
Use extra caution in wind-affected terrain and continue to avoid steep, rocky slopes with shallow snow cover.
Confidence
Moderate
Avalanche Summary
On Thursday, several size 1-2 wind slab avalanches were reported across the Eastern Purcells.
On Monday several human-triggered and natural avalanches were reported in the Jumbo area west of Invermere.
Looking to the weekend, we suspect wind slabs to remain possible to trigger, especially where they overlie a layer of surface hoar.
Snowpack Summary
A thin layer of recent snow has covered a variety of surfaces, including sun crust, surface hoar, and wind-affected snow. Recent winds have varied in direction, forming wind slabs on lee slopes.
Older wind slabs may still be found near ridgetops covering a 20 to 30 cm deep surface hoar layer from early January. These slabs may remain sensitive for an extended period.
A weak layer of facets buried in early December is on average 60 to 90 cm deep. In the shallower eastern parts of the Purcells, this layer may only be 30 cm deep. This layer continues to cause sporadic large avalanches.
The snowpack base consists of a thick crust and facets in many areas.
Weather Summary
Friday Night
Partly cloudy. 15 to 30 km/h northwest ridgetop wind. Treeline temperature -16 °C.
Saturday
Mostly sunny. 5 to 15 km/h variable ridgetop wind. Treeline temperature -20 °C.
Sunday
Mostly sunny. 15 to 20 km/h north ridgetop wind. Treeline temperature -21 °C.
Monday
Sunny. 10 km/h west ridgetop wind. Treeline temperature -18 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
- Pay attention to isolated wind affected features in the alpine, as well as cross-loaded features at treeline.
- Be aware of the potential for large avalanches due to buried weak layers.
Avalanche Problems
Wind Slabs
Recent winds have varied in direction, use caution when entering any wind-affected terrain. These slabs are expected to be most reactive where they overlie facets, surface hoar or a melt-freeze crust.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2
Persistent Slabs
The early December weak layer remains a concern in areas with a shallow snowpack, particularly on steep rocky slopes.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1.5 - 3