Avalanche Forecast

Issued: Jan 11th, 2015 8:26AM

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.

Wind slabs are still on the radar as the number one concern at this time.

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

A weak upper level trough will approach 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 to2000m before coming back down on Thursday.

Avalanche Summary

Numerous radiation triggered sloughs were reported yesterday on steep south aspects, and 1 size 2 avalanche was reported on a South East aspect in steep un-skiable terrain.

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.

Problems

Wind Slabs

Moderate to strong S-SW winds above 1000m will form wind slabs on lee slopes at upper elevations

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

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Persistent Slabs

A small avalanche could produce enough force to trigger a deeply buried instability.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 5

Valid until: Jan 12th, 2015 2:00PM