Avalanche Forecast

Issued: Feb 21st, 2016 8:54AM

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

Avalanche Canada esharp, Avalanche Canada

A couple of recent deep slab avalanches in the north of the region are keeping Alpine danger ratings elevated.

Summary

Confidence

Moderate

Weather Forecast

MONDAY: light flurries overnight becoming mainly cloudy through the day, moderate westerly winds, freezing level 1000m. TUEDSAY: partly cloudy, moderate southerly winds, freezing level 800m. WEDNESDAY: partly cloudy, moderate westerly winds, freezing level 1200m.

Avalanche Summary

A couple skier triggered wind slab avalanches were reported on Saturday. In the north of the region, deeply buried persistent weak layers in the alpine have recently woken up with several large avalanches releasing on basal facets in the last week. This weak layer has be reactive to skier triggering from a thin spots or heavy triggers such as a smaller avalanches and cornice failure.

Snowpack Summary

Settling storm snow overlies a melt freeze crust buried on February 12th that extends up to around 2000m elevation. This snow is reported to be bonding well to the crust. Moist snow can be found at lower elevations and on slopes that see direct sun. Recent winds have redistributed the surface snow at higher elevations. Older wind slabs can be found on east aspects while reverse loading may have loaded lee features on the west.  The early January surface hoar/facet layer can be found between 50cm and 1m down and remains a concern. This layer seems the most reactive in the north of the region but may still be a problem in the south as well. Shallow snowpack areas in the east and north of the region have a weak base layer of facetted snow on or just above the ground.

Problems

Wind Slabs

An icon showing Wind Slabs
Reactive slabs may be found on freshly wind loaded alpine features. Smaller avalanches have the potential to step down to buried week layers.
Be alert to conditions that change with elevation. >Stay off recent wind loaded areas until the slope has had a chance to stabilize. >

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Persistent Slabs

An icon showing Persistent Slabs
Several buried weak layers remain a concern. Surface hoar can be found in many areas while several large avalanches have recently released on facets near the ground further north.
Be aware of the potential for large, widely propagating avalanches due to the presence of buried surface hoar.>Avoid convexities or areas with a thin or variable snowpack.>Be aware of thin areas that may propogate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Feb 22nd, 2016 2:00PM