Avalanche Forecast
Regions: Crawford, Dogtooth, East Purcell, Purcells, West Purcell.
Seek out wind sheltered terrain below treeline for the softest snow and lowest hazard.
Use extra caution in wind-affected terrain and avoid steep, rocky slopes with shallow snow cover.
Confidence
Moderate
Avalanche Summary
On Thursday and Friday, 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 forward, we suspect wind slabs will remain possible to trigger, especially where they overlie a layer of surface hoar.
Snowpack Summary
Recent strong to extreme winds from shifting directions have created wind slabs of varying hardness and thickness on lee slopes. These slabs may be overlying a variety of surfaces, including sun crust, surface hoar, and facets.
A surface hoar layer from early January, buried 20–40 cm deep, may be reactive to human triggers, particularly where it is covered by a wind slab.
A persistent weak layer of facets buried in early December is on average 60 to 90 cm deep. In areas near Invermere this layer may only be buried 30 cm. Triggering this layer remains possible in isolated areas.
The snowpack base consists of a thick crust and facets in many areas.
Weather Summary
Saturday Night
Partly cloudy. 30 to 50 km/h northwest ridgetop wind. Treeline temperature -18 °C.
Sunday
Sunny. 20 to 40 km/h north ridgetop wind. Treeline temperature -19 °C.
Monday
Sunny. 50 km/h northwest ridgetop wind. Treeline temperature -20 °C.
Tuesday
A mix of sun and cloud. 60 km/h west ridgetop wind. Treeline temperature -16 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Carefully evaluate steep lines for wind slabs.
- Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
- Be aware of the potential for large avalanches due to buried weak layers.
- Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.
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