Avalanche Forecast

Issued: Jan 17th, 2013 8:06AM

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.

Parks Canada jon schleiss, Parks Canada

Warm temperatures at treeline and in the alpine are contributing to slab formation and weakening cornices. Be cautious where you can feel new windslabs, and near cornices in periods of warm temperatures or solar radiation.

Summary

Weather Forecast

Light flurries will produce no significant amounts of snow for today and Friday. An above freezing layer of warm air between 1500m and 2500m combined with sunny breaks could warm the snowpack rapidly today. No new snow on the forecast for the next few days.

Snowpack Summary

Warm temperatures in the alpine (inversion) combined with moderate to strong SW winds are continuing to create hard and soft slabs, especially in the alpine.  These slabs overlie the January 4 interface, down 40-60cm.� Steep solar aspects are most reactive due to facets on a crust.  Significant loading should also be expected on NE aspects.�

Avalanche Summary

Most reported avalanches have occurred on S and W aspects in the alpine, and are associated with the January 4 sun crust.  Pockets of wind slab have also been observed to fail in specific terrain, mostly on cross loaded features.  Cornices are beginning to fail, causing avalanches to size 2.5.

Confidence

Problems

Wind Slabs

An icon showing Wind Slabs
Strong SW winds combined with very mild temperatures in the alpine (0 degrees at 2000m for 2 days) are contributing to wind slab development.� Lee and cross-winded features (NE aspects) will be most loaded, however all aspects are suspect.
Avoid freshly wind loaded features.Stay well to the windward side of corniced ridges.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Persistent Slabs

An icon showing Persistent Slabs
The January 4 crust-facet interface (down 60 cm) remains a concern.� It is most problematic on steep S and W aspects.� The slab above this is becoming more cohesive, and skier triggering remains likely.
The best powder will be found in sheltered locations at or below treeline.Stay well back from cornices.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Jan 18th, 2013 8:00AM