Archived

Avalanche Forecast

Jan 12th, 2015–Jan 13th, 2015

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

1: Low

The avalanche danger rating below treeline will be low

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

1: Low

The avalanche danger rating below treeline will be low

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

1: Low

The avalanche danger rating below treeline will be low

Regions: Northwest Coastal.

The December week may still be reactive to moderate loads. Continue to make conservative choices as the new snow with wind comes into the region.

Confidence

Good - Intensity of incoming weather systems is uncertain

Weather Forecast

A weak upper level trough will arrive on the coast on Monday bringing flurries to the region. As the trough moves inland on Tuesday, the North coast may see up to 25 cm of snow at higher elevations, and the possibility of rain up to 1500m. Winds will be light to moderate from the south throughout the forecast period. Wednesday will see a bit of clearing before the next pulse of moisture arrives later in the day. Freezing levels around 500m until Wednesday, when they will spike to 2000m before coming back down on Thursday.

Avalanche Summary

No avalanches reported yesterday.

Snowpack Summary

Strong winds have redistributed the recent storm snow, and rain in some areas has produced a surface crust layer that will be of concern with future snow loading. A buried surface hoar layer in the mid-snowpack is still on the radar in some northern sections , and the mid December crust can still be found in the middle of the snowpack. This layer has been reported to be sandwiched between facets and surface hoar in some places. The November crust near the bottom of the snowpack is generally well bonded but may still be reactive in areas with shallow snowpack.

Avalanche Problems

Wind Slabs

Moderate to strong S-SW winds will build windslabs in lee features, especially N and NE facing terrain.

Be careful with wind loaded pockets while approaching and climbing ice routes.>Use caution in lee areas in the alpine. Recent wind loading has created wind slabs.>Be cautious as you transition into wind affected terrain.>Assess start zones carefully and use safe travel techniques.>

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 3

Persistent Slabs

A small avalanche or cornice failure could produce enough force to trigger this buried weak layer.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.>Use caution around convexities, ridge crests, rock outcroppings and anywhere else with a thin or variable snowpack.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 5