Avalanche Forecast

Issued: Apr 23rd, 2012 4:00PM

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

Avalanche Canada triley, Avalanche Canada

Daily bulletins with danger ratings are finished for the season for this region. General advice can be found in the Avalanche Problems section and on the Forecast Details tab below. Additional information can be found in the Forecaster Blog.

Summary

Weather Forecast

Avalanche Summary

Spring conditions exist in the region. Avalanches are most likely to occur in response to solar radiation, warm temperatures, and periods of rain. Particularly dangerous conditions may develop during prolonged periods of warming, heavy rain, or on days with no overnight freeze. Under these conditions, surface avalanches may step down and trigger deeper wet slab avalanches. Prolonged warming may also weaken large and destructive cornices. Large cornice releases are dangerous, and may act as a heavy trigger on the slope below. Typically, avalanche activity increases during the day and is at a peak during the afternoon. If it's raining or there was no overnight freeze, avalanche activity can happen at any time.

Snowpack Summary

As we transition into spring, the surface layers have a great deal of influence on the snowpack. When there is a solid re-frozen surface crust, travel is fast and easy, and the snowpack is held together by the surface cap. Surface layers and any deeper persistent weak layers are unlikely to fail until the surface cap breaks down from daytime heating. During warm conditions, melt water is able to percolate within the snowpack and cause surface layers and any deeper weak layers to fail. If it cools off and snows, new snow may not bond well to the hard spring crusts, and isolated storm and wind slabs can easily develop.

Problems

Loose Wet

An icon showing Loose Wet
Loose wet avalanches are most likely on steep slopes as temperatures rise or when there is no overnight freeze. Prolonged exposure to sunshine or rainfall may cause this problem to become more widespread and include low angled slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 9

Wet Slabs

An icon showing Wet Slabs
Prolonged warming may weaken the snowpack and cause wet slab avalanches. These could fail on buried spring crusts, deeply buried persistent weak layers, or on the ground, potentially creating very large avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 9

Valid until: Nov 15th, 2012 3:00PM