Archived

Avalanche Forecast

Dec 18th, 2016–Dec 19th, 2016

Alpine

4: High

The avalanche danger rating in the alpine will be high

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: Sea To Sky.

Forecast snow amounts vary throughout the region. The danger ratings as seen reflect the high end of the estimates.

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

Monday: Snow, accumulations from Sunday night through Monday 20-35cm / Moderate to strong southwest wind / Alpine temperature -5 Tuesday: Flurries, accumulations 5cm / Moderate to strong southwest wind / Alpine temperature of -2Wednesday: Cloudy with scattered flurries / Moderate southwest wind / Alpine temperature -2

Avalanche Summary

Expect avalanche activity to rise with new snowfall accumulating Sunday night through the day Monday combined with moderate to strong wind and warming temperatures.

Snowpack Summary

20-30cm of new snow overlies the previous variable snow surface from last week, which includes hard wind pressed or scoured areas, old wind slabs, weak faceted snow, or surface hoar. Moderate to strong southwest have redistributed this new snow to form windslabs in the lee of terrain features in the alpine and treeline. The widespread mid-November crust is typically down 1-2m in the snowpack. Recent snowpack and explosive tests have shown the crust to be unreactive, but it could remain a problem in shallow alpine start zones.

Avalanche Problems

Storm Slabs

New snow combined with moderate to strong southwest winds have created slabs on top of a variety of potential weak sliding layers.

Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.Minimize exposure during periods of heavy loading from new snow and wind.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 3