Avalanche Forecast
Regions: Kootenay Boundary, Bonnington, Grohman, Kootenay Pass, Norns, Rossland, Ymir, Moyie, Crawford.
Continue to choose simple, mellow terrain. Signs of buried weak layers may be hard to find.
Be especially cautious on high north-facing slopes, and on sunny slopes during warming.
Confidence
Moderate
Avalanche Summary
No new avalanches have been reported since Sunday.
Looking forward: Avalanches on buried weak layers may be difficult to trigger, but if one is triggered, it is likely to be large and destructive.
Snowpack Summary
5 to 15 cm of new snow is settling over a widespread melt-freeze crust that exists everywhere but high north-facing slopes.
Two concerning weak layers are present in the mid snowpack: facets/surface hoar or a crust from mid-February buried 40-60 cm, and faceted snow/surface hoar/crust from late January buried 60-100 cm. These layers were active during the warm-up and are most concerning at upper elevations, where a thick and supportive crust under the new snow hasn't stabilized the snowpack.
Weather Summary
Wednesday Night
Mostly clear. 5 to 10 km/h north wind. Freezing level falling to between 1000 m and valley bottom. Treeline low around -6 °C.
Thursday
Sunny. 10 to 15 km/h northeast ridgetop wind. Freezing level rising to 1800 m. Treeline high around -2 °C.
Friday
Sunny. 5 to 10 km/h northwest ridgetop wind. Freezing level falling to valley bottom overnight, rising to 1900 m.
Saturday
Partly cloudy. 15 to 30 km/h southwest ridgetop wind. Freezing level falling to valley bottom overnight, rising to 1700 m.
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.
- Use caution above cliffs and terrain traps where even small avalanches may have severe consequences.
- In times of uncertainty, conservative terrain choices are our best defense.
- A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
Avalanche Problems
Persistent Slabs
Weak layers exist 40 to 100 cm deep. These layers remain a concern where there is no thick, supportive crust under the new snow.
Aspects: North, North East, East, West, North West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1.5 - 3
Loose Wet
Wet loose avalanches will become likely if the sun is out for prolonged periods. Avoid overhead hazard from sun-exposed slopes, especially if the snow surface is moist or wet.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood: Likely
Expected Size: 1 - 2