Avalanche Forecast

Issued: Jan 10th, 2015 8:32AM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs and Persistent Slabs.

bcorrigan, Avalanche Canada

Northwest Coastal.

Conditions are improving, but windslabs remain a concern at treeline and above.

Summary

Confidence

Good - Due to the number and quality of field observations on Monday

Weather Forecast

Cloudy with cool temperatures and small amounts of new snow in the forecast for the next few days, then the arctic ridge of high pressure will rebuild and again dominate the Province bringing even cooler temperatures and very little precipitation.

Avalanche Summary

2, size 2.5 naturally occuring wind slab avalanches were reported yesterday on west facing slopes around 1500 metres. Reports of natural avalanche activity re slowing down, but the potential for rider triggering remains a concern.

Snowpack Summary

Storm snow amounts vary widely across the region. Southern areas received close to 1m of new snow, but northern areas reported receiving half of that. 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.

Problems

Wind Slabs

Dribs and drabs of new snow may form into thin windslabs on lee slopes

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: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

The slab will gain strength and should bond as time goes on, however, the weak layer still exists in the mid snow pack. A cornice failure or small avalanche could trigger this layer and produce a large destructive avalanche.

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 - 6

Valid until: Jan 11th, 2015 2:00PM