Archived

Avalanche Forecast

Dec 8th, 2016–Dec 9th, 2016

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

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

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Purcells.

Changing wind directions may deposit snow in unusual locations. Constantly evaluate the conditions as they change with elevation and aspect.

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

Some cloud developing overnight combined with light southerly winds and alpine temperatures around -20. Mostly cloudy on Friday with a chance of sunny breaks. Winds becoming moderate from the southwest during the day with alpine high temperatures around -17. Light snow on Saturday with moderate southwest winds and alpine temperatures around -15. Light snow on Sunday with moderate southwest winds.

Avalanche Summary

No new avalanches reported from this region. I suspect that pockets of wind slab may become more stubborn to trigger, but also may propagate further once they are released.

Snowpack Summary

Recent snow has formed wind slabs on northerly aspects in the alpine that are reactive to light additional loads like a single skier/rider. The cold temperatures and clear skies are developing near surface facets, and may be preserving surface hoar that was buried on the weekend. Alpine snow depths are around 120-170 cm, and the widespread mid-november crust is buried down around 70-90 cm. Snowpack and crust depths increase as you move west into the Selkirks. It sounds like there is a bit less snow on the ground in the south of the region, but we have not had many observations at this time. If you dig down to the crust, watch for facets developing above and below that may provide a hard surface with a weak sliding layer in the future. Please let us know what you find by posting to the MIN (Mountain Information Network).

Avalanche Problems

Wind Slabs

Cold temperatures and variable winds have preserved pockets of wind slab in the alpine and at treeline.

Use ridges or ribs to avoid pockets of wind loaded snow.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2