Kootenay Boundary

Triggering persistent slabs remains possible, especially in wind-loaded areas.

Retreat to more conservative terrain if you experience signs of instability.

On Wednesday a rider remotely triggered a persistent slab avalanche (size 2) on an east-facing slope just above 2000 m. The party indicated that they felt whumpfing on the approach as they left treeline. (See photo below) Dry loose sluffing continues to be observed from steep terrain features.

Rider triggering remains possible at all elevations where a stiffer slab exists above the late January buried weak layers.

Exposed terrain in the alpine and treeline is variably wind-affected. Up to 5 cm of new snow from Thursday night may be covering a layer of surface hoar in many areas, or a thin suncrust on steep south-facing slopes.

20 to 60 cm of faceted snow overlies a weak layer from late January. This layer consists of a crust on sun-exposed slopes and surface hoar on all other aspects. Recent snowpack tests indicate that an overlying stiff and consolidated slab is generally required for it to be reactive.

The mid and lower snowpack is generally well settled.

Friday Night

Cloudy with isolated flurries. 30 km/hnorthwest ridgetop wind. Treeline temperature -10 °C.

Saturday

A mix of sun and cloudy. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -10 °C.

Sunday

Cloudy with flurries up to 5 cm. 15 to 25 km/h south ridgetop wind. Treeline temperature -9 °C.

Monday

Cloudy with 0 to 2 cm. 15 to 25 km/h north ridgetop wind. Treeline temperature -7 °C.

More details can be found in the Mountain Weather Forecast.

• Be careful as you transition into wind-affected terrain.
• Approach steep and open slopes at and below treeline cautiously, as buried surface hoar may exist.
• Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.
• Watch for signs of instability like whumpfing, hollow sounds, shooting cracks, or recent avalanches.