Avalanche Forecast
Regions: Bonnington, Crawford, Grohman, Kokanee, Kootenay Boundary, Kootenay Pass, Moyie, Norns, Retallack, Rossland, Valhalla, Whatshan, Ymir.
Conservative terrain selection is highly recommended.
Choose gentle, low consequence lines and avoid overhead hazard, especially during periods of sun.
Confidence
No Rating
Avalanche Summary
Tues/Wed: Several size 1-1.5 natural and skier-triggered storm and wind slab avalanches occurred.
Mon: A few natural and skier triggered storm slab and wind slab avalanches were reported up to size 2.5 (very large). Some of these avalanches stepped down to persistent weak layers.
Looking forward: Storm slabs are expected to remain reactive and may step down to deeper persitstent weak layers.
Snowpack Summary
15 to 40 cm of new snow fell in the last storm creating widespread and reactive storm slabs. The new snow may overload persistent weak layers in the upper to mid snowpack. There is strong potential for storm slabs to step down to these deeper layers which include:
Facets/surface hoar/crust from early March buried 25-50 cm.
Facets/surface hoar/crust from mid-February buried 40-90 cm
Facets/surface hoar/crust from late January buried 80-120 cm.
The rest of the snowpack is well settled with no other layers of concern.
Weather Summary
Thursday Night
Cloudy with 0 to 15 cm of snow. 20 to 30 km/h southwest ridgetop wind. Treeline temperature -9 °C.
Friday
Mix of sun and cloud. 15 to 20 km/h southwest ridgetop wind. Treeline temperature -7 °C.
Saturday
Cloudy with 5 to 15 cm of snow. 30 km/h south ridgetop wind. Treeline temperature -5 °C.
Sunday
Mostly cloudy with 0 to 2 cm of snow. 15 km/h variable ridgetop wind. Treeline temperature -5 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Be aware of the potential for large, destructive avalanches due to deeply buried weak layers.
- Be aware of the potential for human triggerable storm slabs at lower elevations, even on small features.
- Even brief periods of direct sun could produce natural avalanches.
Avalanche Problems
Storm Slabs
Up to 40 cm of new snow has fallen in the region and is expected to take a few days to bond. Storm slabs may overload deeper weak layers causing large and destructive avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely - Very Likely
Expected Size: 1 - 2
Persistent Slabs
Several persistent weak layers exist in the upper meter of the snowpack. The greatest concern for triggering these layers lies in areas where a thick, supportive crust is absent under the new snow.
Aspects: North, North East, East, West, North West.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1.5 - 3