Kootenay Boundary

With snow available for transport and wind in the forecast, wind slabs will be developing throughout the day. Monitor the wind direction and anticipate slopes where newly formed wind slabs may exist.

After a dynamic period of large avalanches occurring on deep persistent weak layers, reported avalanche activity has tapered.

Going forward, snow available for transport may build touchy wind slabs over various surfaces.

Forecasted flurries overnight will further bury various surfaces of crust on steep south-facing slopes, surface hoar that developed over the past few days, and 30 to 40 cm of previous snow. A hard melt-freeze crust can be found up to 2000 m. Where it is robust enough to do so, this crust appears to be effectively bridging deeper instabilities, making them more difficult to trigger.

The two persistent weak layers are a 60 to 80 cm deep surface hoar/crust layer that was buried in mid-December and an 80 to 150 cm deep surface hoar/facet layer buried in mid-November.

Thursday night

Cloudy with 5 cm of new snow, 30 km/h south winds, treeline temperature around -4 °C.

Friday

Cloudy with 5 to 10 cm new snow, 20 to 30 km/h southwest wind, treeline temperature around -5 °C, freezing level 800 m.

Cloudy, up to 10 cm of new snow, southeast wind easing to 15 to 20 km/h, treeline temperature -5 °C, freezing level 800 m.

Cloudy, up to 5cm of new snow, 20 to 30 km/h south winds, treeline temperatures -5 °C

More details can be found in the Mountain Weather Forecast.

• Pay attention to the wind, once it starts to blow fresh sensitive wind slabs are likely to form.
• Be mindful that deep instabilities are still present and have produced recent large avalanches.