Avalanche Forecast

Issued: Apr 19th, 2014 9:11AM

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

esharp, Avalanche Canada

South Columbia.

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 the recent 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 Sunday. Convective flurries may be possible. The ridge shifts eastward as the next system moves in over the region Monday night.Tonight and Sunday: Light precipitation overnight (up to 10cm) then clearing / Moderate then light westerly winds / Freezing levels 2000mMonday: Partly cloudy with a chance of flurries / Moderate southwesterly winds / Freezing levels up to 2400m Tuesday: Flurries (5-15 cm) / Light southerly winds / / Freezing levels between 1900 and 2400m

Avalanche Summary

There have been recent reports of small wind slab avalanches releasing on steep wind loaded features.. At lower elevations and on solar aspects small loose wet avalanche continue to be triggered on steep slopes.

Snowpack Summary

Up to 30 cm of recent storms snow is rapidly settling and appears to be bonding well to a supportive crust that can be found on all aspects and elevations except for high elevation north-facing terrain. 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 avalanche

Problems

Loose Wet

Expect to see an increase in avalanche activity 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.>Cornices become weak with daytime heating, so travel early on exposed slopes.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Wind Slabs

Wind slabs immediately lee of ridge crest may be sensitive to human triggering.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Apr 20th, 2014 2:00PM