Avalanche Forecast
Regions: East Purcell, Purcells, St. Mary.
Stay vigilant, as conditions may change rapidly.
Expect significant variability based on elevation, aspect, and exposure to wind and sun.
Confidence
Moderate
Avalanche Summary
Fri: Several large to very large (size 2-3) persistent slab avalanches occurred in the region. All of them initiated in the alpine.
Thurs: A large (size 2) naturally-triggered persistent slab near Invermere and a size 2.5 persistent slab near Kimberley were observed.
Tues: Avalanche control produced large avalanches (up to size 3.5) in the central-western part of the region.
Looking forward: Wind slabs and persistent slabs are expected to remain triggerable on Sunday.
Snowpack Summary
30 - 50 cm of new snow accumulated in the region over the last few days. This snow covers a crust on sunny slopes and lower elevations, and surface hoar or facets on sheltered and shady upper elevations. Alpine and treeline areas have experienced southwesterly winds that built slabs on lee north and east-facing slopes.
Several persistent weak layers consisting of a crust, facets or surface hoar from February and January remain a concern, buried 50 to 100 cm. In many areas, facets or depth hoar also make up the base of the snowpack.
Weather Summary
Sunday Night
Partly cloudy with isolated flurries up to 2 cm. 15 to 30 km/h west ridgetop winds. Treeline temperature -9 °C.
Monday
Mostly sunny. 10 to 25 km/h southwest ridgetop winds. Treeline temperature -5 °C.
Tuesday
Mostly sunny. 10 to 20 km/h west ridgetop winds. Treeline temperature -6 °C.
Wednesday
Sunny. 10 to 25 km/h south ridgetop winds. Treeline temperature -1 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be aware of the potential for large, destructive avalanches due to deeply buried weak layers.
- Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
- If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
- Avoid steep, sun-exposed slopes when the air temperature is warm or when solar radiation is strong.
Avalanche Problems
Persistent Slabs
Several persistent weak layers exist within the snowpack and have been the cause of recent large avalanches in the region. The greatest concern for triggering these layers is on upper elevation north and east facing slopes.
Aspects: North, North East, East, West, North West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 2 - 3
Wind Slabs
New snow overlies a variety of surfaces, including surface hoar, facets, or a crust, which may make wind slabs more reactive and take longer to bond.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Loose Wet
Wet loose avalanches will be likely on sun-exposed slopes. Avoid overhead hazard from steep sunny faces during the warmest parts of the day.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood: Likely - Very Likely
Expected Size: 1 - 2