Avalanche Forecast

Issued: Dec 3rd, 2017 4:17PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Storm Slabs.

mgrist, Avalanche Canada

Kootenay Boundary.

The lure of powder slopes and sunny skies will be strong as the weather clears. Take a cautious approach towards more aggressive terrain - especially steep, wind-affected terrain.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

A clearing trend will result in fine weather for the foreseeable future. Monday: Cloudy with sunny periods. Freezing levels around 700 m. Light northwesterly winds.Tuesday: Mainly sunny and warming up. Freezing levels rising to 1500 m. Light northerly winds.Wednesday: Sunny and warm. Light northerly winds. Freezing levels 1000m.

Avalanche Summary

On Saturday a Size 1 skier-triggered avalanche was reported on an unsupported steep gully feature near Nelson. See here for the MIN report. On Thursday we had a report of a skier-triggered Size 1 storm slab at 2000m on a north west aspect near Nelson. See here for the MIN report. The recent storm snow has been reactive to ski cutting, especially lee features which have seen wind loading.We currently have very limited observations in this region. Please submit your observations to the Mountain Information Network (MIN).

Snowpack Summary

30 - 50cm of new snow has fallen in the past week. At higher elevations, south through west winds (gusting strong at times) redistributed the new snow, forming wind slabs on lee features.Below the recent storm snow you'll likely find a couple of widespread crusts which formed as a result of late November's rain. The depth of the snowpack varies greatly with elevation. Recent reports suggest the average depth is 100-170cm in the alpine, 50-100cm at treeline, and decreasing rapidly below treeline where the primary hazards are rocks, stumps, and open creeks. We currently have very limited snowpack observations within this region and it is critical to supplement this information with your own observations.

Problems

Storm Slabs

Recent wind and snowfall formed storm slabs, which may be more reactive in heavily wind-exposed terrain, or in areas where the new snow has a weak bond with underlying crusts.

The new snow may require several days to settle and stabilize.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 4th, 2017 2:00PM