Avalanche Forecast

Issued: Apr 22nd, 2012 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Loose Wet, Wet Slabs and Cornices.

Avalanche Canada jlammers, Avalanche Canada

Summary

Confidence

Fair - Timing or intensity of solar radiation is uncertain

Weather Forecast

Broken cloud is forecast for Monday with the possibility of light rain in the afternoon, particularly in the north of the region. Ridgetop winds are expected to be moderate from the southwest with freezing levels sitting at about 3000m.

Avalanche Summary

Widespread wet snow avalanches to size 2 were reported from the region over the weekend. Large cornice fall at 2400m was also reported releasing a size 2 slab. Continued wet avalanche activity is expected on Monday with forecast high freezing levels.

Snowpack Summary

On Thursday night, light to locally moderate amounts of snow fell forming wind slabs that have settled considerably or turned to wet slabs with warming over the weekend. The recently fallen snow overlies melt-freeze crust sandwiches and wet grains at treeline and in the alpine while warm temperatures continue to penetrate and weaken the isothermal snowpack at lower elevations. The mid-February buried surface hoar layer is down about 140-220 cm. The likelihood of avalanches failing on this layer has been very low due to cooler temperatures, however it may wake up with warming and the consequence continues to be very large destructive avalanches. Cornices in the region are very large and have may become weak with spring temperatures.

Problems

Loose Wet

An icon showing Loose Wet
Loose wet snow avalanches are expected with continued warming on Monday. Watch for increased activity in steep, sun-exposed rocky terrain. Loose snow avalanches can be pushy and may entrain a great deal of mass.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 5

Wet Slabs

An icon showing Wet Slabs
With continued warming wet slab avalanche activity becomes more likely. In the upper snowpack, there are a variety of crusts that may act as a suitable sliding surface for wet slab avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 5

Cornices

An icon showing Cornices
Forecast warm temperatures will weaken cornices. Cornices may be destructive by themselves, and may also trigger avalanches on the slope below.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 5

Valid until: Apr 23rd, 2012 9:00AM