Avalanche Forecast

Issued: Feb 20th, 2016 8:40AM

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

Avalanche Canada esharp, Avalanche Canada

Moderate winds are expected to form touchy fresh wind slabs in exposed terrain on Sunday.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

SUNDAY: partly cloudy with flurries starting in the afternoon, up to 5cm expected overnight, moderate southwesterly winds, freezing level of 1000m. MONDAY: lingering flurries with sunny breaks, moderate northwest winds, freezing level of 1000m. TUESDAY: mainly sunny, light south east winds, freezing level of 800m.

Avalanche Summary

No new avalanches have been reported recently although I suspect wind slabs are still touchy. If the sun comes out, natural avalanches are possible on steep south facing terrain features. In the far north, deeply buried persistent weak layers may still be reactive to large triggers such as a small avalanche stepping down or a cornice failure.

Snowpack Summary

Settling storm snow overlies a melt freeze crust buried on February 12th that extends up to around 2000m elevation. The upper snowpack is reported to be bonding well to this crust. Moist snow can be found at lower elevations and on solar aspects. Recent wind has redistributed the surface snow at higher elevations forming wind slabs in lee features. The early January surface hoar/facet layer is down around 1 meter 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

Storm Slabs

An icon showing Storm Slabs
Reactive slabs are likely to be found on freshly wind loaded alpine features and south facing slopes when the sun comes out.
Stay off recent wind loaded areas until the slope has had a chance to stabilize. >Be alert to conditions that change with elevation. >

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Buried weak layers remain a concern, especially in the far north of region.  Large avalanche can be triggered from thin spots and cornice releases, or smaller avalanches have the potential to step down.
Avoid convexities or areas with a thin or variable snowpack.>Be aware of the potential for large, widely propagating avalanches due to the presence of buried surface hoar.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

3 - 6

Valid until: Feb 21st, 2016 2:00PM