Avalog Join
Archived

Avalanche Forecast

Dec 12th, 2016–Dec 13th, 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
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
1: Low
The avalanche danger rating at treeline will be low
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Regions: Sea To Sky.

It's all about the wind! Best avoid steep slopes where recent winds have blown new snow into pillowy slabs.

Confidence

Moderate - Wind effect is extremely variable

Weather Forecast

Tuesday, Wednesday and Thursday: Cold and dry and mostly clear throughout the period. Treeline temperatures in the -8 to -10C range, winds light, initially from the northeast, becoming easterly on Wednesday. Some cloud appearing Thursday.

Avalanche Summary

On Sunday, a small cornice was human-triggered and loose snow avalanches were noted in steeper terrain. Otherwise no notable avalanche activity occurred. On Saturday, ski cutting was producing very soft slabs, in leeward terrain features and a few natural size 1 loose avalanches were also observed.

Snowpack Summary

Around 20cm of new low density snow has buried the heavily wind affected surfaces from the strong outflow winds last week. The old surface is highly variable and may include hard wind pressed or scoured areas, old wind slabs, weak faceted snow, or small surface hoar. Expect the new snow to be bonding poorly with this interface. The cold temperatures appear to be preserving the old wind slabs from the end of last week and they still may be reactive to human triggering in isolated areas. In high elevation terrain, moderate southwest winds over the weekend may have redistributed some of the new storm snow and soft slabs may exist in immediate leeward features. 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

Wind Slabs

Winds slabs may be lingering on all aspects due to recent winds from a variety of directions. These wind slabs may be sitting over a weak layer which could increase their reactivity.
Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2