Archived

Avalanche Forecast

Dec 4th, 2017–Dec 5th, 2017

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: 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.

Confidence

Moderate - Freezing levels are uncertain

Weather Forecast

A clearing trend will result in fine weather for the foreseeable future.Tuesday: Mainly sunny and warming up. Freezing levels 1000m, alpine high temperatures of -4 Celsius. Light northerly winds.Wednesday: Sunny. Light northerly winds. Freezing levels 2000m. Thursday: Sunny and warm. Freezing levels around 3000 m. Light northwesterly winds.

Avalanche Summary

On Sunday we had reports of natural and skier triggered storm slab avalanches to Size 2 near Nelson. See here for the MIN report. On Saturday a Size 1 skier-triggered avalanche was reported on an unsupported steep gully feature near Nelson. See here for the MIN report. The recent storm snow has been reactive to ski cutting, especially down wind (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 (2 to 5 cm thick) 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.

Avalanche 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.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2