Archived

Avalanche Forecast

Dec 22nd, 2016–Dec 23rd, 2016

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

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: South Coast Inland.

As this past week's storm snow continues to settle it will still be important to evaluate the bond between the old snow surface and the new snow. There is still potential for a weak sliding layer in isolated sheltered areas.

Confidence

High - The weather pattern is stable

Weather Forecast

Friday: Mainly cloudy / Light northerly wind / Alpine temperature -9Saturday: Sunny with cloudy periods/ Light northeast wind / Alpine temperature -10Sunday: Mix of sun and cloud / Light west wind / Alpine temperature -10

Avalanche Summary

Reports in the Duffy Lake area on Tuesday indicate a few natural avalanches running to size 2 in the alpine. I would suspect there to be continued potential for skier and rider triggering with recent strong winds creating wind slabs at upper elevations and a possible weak bond at the storm/old snow interface with the possibility of buried surface hoar in isolated sheltered areas.

Snowpack Summary

30-60cm 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. New wind slabs that have formed in response to southwest winds. In the Duffey Lake area, recent snowpack tests gave hard sudden results down 60 cm at the interface between the recent storm snow and old snow on rounding faceted crystals. The widespread mid-November crust is typically down approximately 1-1.5m. Recent snowpack tests have shown the crust to be unreactive, but it could become a problem in shallow alpine start zones.

Avalanche Problems

Wind Slabs

Moderate to strong southwest winds have created wind slabs in the lee of terrain features

Watch for signs of instability such as whumpfing, or cracking. Use ridges or ribs to avoid pockets of wind loaded snow.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2