Avalanche Forecast

Issued: Apr 8th, 2013 8:15AM

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

ali haeri, Parks Canada

Glacier.

Summary

Weather Forecast

Cool and unsettled air will pass over the interior today. Little precipitation is expected with overcast skies. A ridge of high pressure builds on Tuesday bringing dry conditions with sun and cloud before a more significant system arrives on Wednesday with freezing levels to rise to 1500m.

Snowpack Summary

10 to15 cm of snow over crusts and moist snow in the alpine and treeline. Supportive melt-freeze crust over moist snow below treeline.

Avalanche Summary

Yesterday: Natural size 3.0 slab avalanche, NW aspect, 2600m, off of Youngs Peak Basin, very wide propagation. Skier triggered size 2.0 slab avalanche, NW aspect, 2750m on Youngs Peak Headwall.In the highway corridor 3 natural slab avalanches from size 2.5 to 3.

Confidence

on Monday

Problems

Wind Slabs

Moderate to strong N-NE winds overnight will have loaded slopes that are typically on the windward side.

Avoid freshly wind loaded features.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

Buried crusts and surface hoar layers in the upper meter of the snowpack may be reactive to a rider triggering from shallow areas where the snowpack is weak.

Be aware of thin areas that may propogate to deeper instabilites.Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Deep Persistent Slabs

Glide cracks, gaping cracks in the snowpack, exist on many slopes and have been failing with the warm temps. They can fail unpredictably and release the entire snowpack to the ground.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Apr 9th, 2013 8:00AM