Kootenay Boundary

Dangerous avalanche conditions exist. Careful snowpack evaluation, cautious route-finding, and conservative decision-making are essential. Recent snow overlies various layers that could produce slab avalanches on steep terrain features.

Over the past week, a few small (size 1) avalanches were reported south of Nelson. There were also reports of whumpfing and cracking suggesting the recent snow is poorly bonded to the mid-November weak layer.

Avalanches on this layer are most likely to be small and found on isolated terrain features, but it will likely become a more serious problem when new snow arrives Tuesday night and Wednesday.

Early season conditions exist with low snow amounts and crusts found at lower elevations and a deeper and drier snowpack approaching 1 m at treeline and alpine elevations.

Around 30 cm of snow overlies a weak layer that formed mid-November that consists of sugary faceted grains, weak surface hoar crystals in sheltered terrain features, and a hard crust on steep sun-exposed slopes.

The remainder of the snowpack is faceted as shown in this MIN, but is likely still intermixed with rocks, brush, and trees.

Wednesday Night

Cloudy with flurries and 1 to 3 cm, 40 km/h wind from the southwest, treeline temperatures -12 °C.

Thursday

Cloudy with snowfall, accumulations of 10 to 15 cm, 70 km/h wind from the southwest, treeline temperatures warm to -9 °C.

Partly cloudy, isolated flurries with trace amounts of snow, light wind from the north, treeline temperatures around -15 °C.

Clear sky no forecast precipitation, 10 km/h variable wind, treeline temperature -10 to -15 °C.

More details can be found in the Mountain Weather Forecast.

• Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
• Remote triggering is a concern, watch out for adjacent and overhead slopes.
• Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.