Kootenay Boundary

7am update: Storm slabs have been touchy. Carefully evaluate how the new snow is bonding to old surfaces. Cautious route-finding and conservative decision-making are essential.

Numerous large storm slab avalanches were reported on Saturday. Several were skier-triggered, including a size 2.5 near Nelson that resulted in serious injury.

On Thursday in the Valhallas, one rider-triggered avalanche (size 1.5) failed on facets near the ground. This was on a steep, shallow, rocky feature.

Expect up to 40 cm of new snow by the end of the day Sunday to be sitting on a variety of old layers including crusts, wind-affected snow, and powder.

The middle of the snowpack contains several crusts buried 50 to 70 cm deep. Facets have been seen above the crusts near Kokanee and Valhalla.

Below that are a couple of layers of surface hoar that have been made difficult to trigger by the thick crusts above. If the crust doesn't exist be sure to investigate these layers.

Snowpack depth at treeline is 100 to 140 cm.

Saturday Night

Cloudy with 10 to 15 cm of snow, variable direction alpine wind 10 to 20 km/h, treeline temperature -9 °C.

Sunday

Cloudy with up to 5 cm of snow, north alpine wind 10 km/h, treeline temperature -10 °C.

Monday

Mostly clear with increasing clouds through the day, a dusting of snow, southwest alpine wind 25 to 35 km/h, treeline temperature -12 °C.

Tuesday

Mostly cloudy with 10 to 20 cm of snow, southwest alpine wind 55 km/h, treeline temperature -7 °C.

More details can be found in the Mountain Weather Forecast.

• Give the new snow time to settle and stabilize before pushing into bigger terrain.
• Use small low consequence slopes to test the bond of the new snow.
• Shooting cracks, whumphs and recent avalanches are strong indicators of an unstable snowpack.