Avalanche Forecast

Issued: Apr 25th, 2015 8:00AM

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

Lydia Marmont, Parks Canada

Glacier.

Early starts and finishes recommended the next few days when the sun is shining. Watch for pockets of windslab especially when traveling on exposed features.

Summary

Weather Forecast

A break between systems will produce a mix of sun and cloud today with alpine temps climbing to just above zero. Cloud cover should build mid afternoon with a chance of convective flurries afternoon and evening. Similar conditions until Wednesday when a sharp upper trough is forecast to approach BC The trough will produce another solid cold front.

Snowpack Summary

At Treeline and above approx 5 - 10 cm of wind affected snow and pockets of soft slab in lee features overlies crust on solar aspects. The April 10 layer - crust on solar and surface hoar on sheltered north aspects - is down 30-60cm. The snowpack is moist on solar aspects and composed of multiple crusts, but still dry on north aspects above ~2000m.

Avalanche Summary

A good crust recover yesterday night and cooler temps during the day resulted in no observed activity yesterday.

Confidence

Problems

Wind Slabs

Strong South winds yesterday morning will have redistributed 5-10cm of recent snow and built pockets of windslab in lee features. This overlies a crust on solar aspects and could be quite reactive.

Use caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Loose Wet

A strong crust formed last night but could break down on solar aspects. Watch for sluffing.

Minimize exposure when the solar radiation is strong, especially if snow is moist or wet.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

Crusts on solar aspects, and surface hoar on shaded slopes, buried down 30-60cm are still a concern. Daytime warming, loose avalanches and skiers can trigger this layer. Cooler temps have slowed natural activity in the past few days.

Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.Test slopes before committing to them.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Apr 26th, 2015 8:00AM