Archived

Avalanche Forecast

Dec 27th, 2016–Dec 28th, 2016

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

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: Lizard-Flathead.

Watch for signs of fresh wind slabs, such as stiff or slabby snow and blowing snow at ridgetops. If you've been out in the mountain please share your obs on the Mountain Information Network (MIN).

Confidence

Moderate - Forecast snowfall amounts are uncertain on Thursday

Weather Forecast

WEDNESDAY: Cloudy with isolated flurries, 40-60 km/h west winds, alpine temperatures -10C.THURSDAY: 10-20 cm of new snow, 60-80 km/h west winds, alpine temperatures -8C.FRIDAY: Cloudy with isolated flurries, 20-40 km/h northwest winds, alpine temperatures -10C.

Avalanche Summary

On Tuesday, new storm snow produced numerous size 1.5-2 avalanches, including natural and skier-triggered loose dry avalanches on north and east aspects.Wind slabs will become the primary concern for human-triggering on Wednesday, with winds forecast to increase. Loose dry avalanches will also be likely in steep features sheltered from the wind.

Snowpack Summary

The region received up to 50 cm of low density snow on Tuesday, which is now available to be redistributed by strong westerly winds. The new snow sits above a variety of surfaces including old hard wind slabs and surface hoar. The cold weather in early December left several layers of weak surface hoar and facets which are now buried 50-80 cm deep. These layers have been inactive for the past week, as it appears the lower snowpack is well-settled. A thick crust rain crust from mid-November is near the bottom of the snowpack and remains well bonded to the surrounding snow.

Avalanche Problems

Wind Slabs

Expect fresh wind slabs to form at higher elevations as winds pick up and redistribute loose snow.

Avoid freshly wind loaded features.Be cautious as you transition into wind affected terrain.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: North, North East, East, South East, South, South West.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2

Loose Dry

With all the unconsolidated low-density snow that has accumulated, I'd be on the look out for loose dry avalanches in gullies and other steep features that were sheltered from the wind.

Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.On steep slopes, pull over periodically or cut into a new line to manage sluffing.Use safe ski cutting techniques before entering steep terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 2