Avalanche Forecast

Issued: Apr 18th, 2014 9:10AM

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

Avalanche Canada esharp, Avalanche Canada

Avalanche danger can quickly rise above what is forecast with warming temperatures and/or brief periods of sun. Be aware of changing conditions and overhead hazards.For more insight into spring danger ratings, check out our Blog Post.

Summary

Confidence

Fair - Due to the number of field observations

Weather Forecast

Synopsis: A weak ridge of high pressure will develop over the interior of the province this weekend.  Convective flurries may be possible.  On Monday the ridge will shift eastward as the next system moves in over the South Coast.Saturday: Sunny with cloudy periods. /  Light southerly winds / Freezing levels between 1000-1500mSunday: Sunny with cloudy periods and a chance of flurries. /  Light westerly winds / Freezing levels between 1800mMonday: Cloudy periods with flurries. /  Light south winds / Freezing levels between 2000m

Avalanche Summary

There have been recent reports of small storm snow avalanches failing on the latest crust in steep terrain.

Snowpack Summary

A recently buried, supportive crust can be found near the surface of the snowpack on all aspects and elevations except for high elevation north-facing terrain. Reactive soft winds slabs may be found in the immediate lee of ridges and ribs.  A second melt-freeze crust buried at the beginning of April can be found down 40-55cm. This layer has been variably reactive in snowpack tests.Three persistent weak layers exist in the highly variable snowpack of the South Columbia region: The mid-March sun crust/surface hoar layer down 50-80cm and the early-March crust/facet/surface hoar layer down around 80-120cm seem to be inactive. The mid-February crust/facet/surface hoar combo is typically down 150 - 200cm. Human triggered avalanches on this layer are unlikely.  Larger triggers such as cornice fall, a smaller avalanche in motion or prolonged warming could wake this layer up, resulting in very large and destructive avalanches.

Problems

Loose Wet

An icon showing Loose Wet
Expect to see an increase in avalanche activity at lower elevations or on solar aspects if the sun comes out for extended periods of time.
Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

An icon showing Wind Slabs
New wind slabs  immediately lee of ridge crest may be sensitive to human triggering.
Avoid wind loaded features, especially slopes immediately lee of ridge crest and mid slope roll overs.>Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
The potential for very large deep slab avalanches needs to remain on your radar. Cornice fall, strong sun, warming temperatures or a surface avalanche in motion could act as triggers.
Be aware of the potential for very large, deep and destructive avalanches due to the presence of deeply buried persistent weak layers.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

4 - 8

Valid until: Apr 19th, 2014 2:00PM