Treeline hazard may be higher near Rossland where buried surface hoar has been more reactive.
Summary
Confidence
Moderate - Freezing levels are uncertain
Weather Forecast
No significant snow or wind in the forecast. The big news is BIG warm up on Tuesday with a temperature inversion and freezing levels possibly rising to near 3000m near Kootenay Pass and 2000m further north in region.
Avalanche Summary
A skier triggered size 1.5 persistent slab avalanche was reported in the Rossland area on Friday. It was at 1700m on an east aspect and failed on a layer of buried surface hoar down approximately 35cm in a cut block.
Snowpack Summary
15-20cm of recent storm snow with moderate to strong southwest winds have created wind slabs that are stubborn, but still possible to human trigger. In isolated locations where winds were the strongest there may be hard slabs that can propagate long distances if triggered. This new snow lies above a variable old surface buried at the end of January. This interface is being reported as a layer of surface hoar at treeline in the Rossland area. However, in most other parts of the region the new snow sits on a rain crust and/or old wind slabs. A weak layer of buried mid January can be found down 45-50cm and seems to be gaining strength. Deeper in the snowpack, the surface hoar layer that was buried earlier in January is now down 80-120 cm and continues to give isolated sudden planar fractures in snowpack tests under heavy loads.
jsmith,
Avalanche Canada
