Avalanche Forecast

Issued: Apr 23rd, 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 Loose Wet and Persistent Slabs.

Lydia Marmont, Parks Canada

Glacier.

Cooler temps forecasted and a freeze to valley bottom last night will cause the spring avalanche activity to slow down. Sunny periods today could still have a strong effect on the upper snowpack.

Summary

Weather Forecast

Mostly cloudy with sunny periods and light SW winds today. No precip expected and freezing levels expected to stay around 2000m. A storm system coming in will move through tonight bringing 5cm of snow. Another system will quickly follow for Friday. A ridge will begin to build over BC starting Saturday bringing warm and dry conditions.

Snowpack Summary

Approx 5cm of snow accumulated yesterday afternoon at tree line and above with good crust recovery below. The snowpack on solar aspects is moist and composed of multiple crusts, while on sheltered north aspects dry snow can still be found above ~2100m. A 30-60cm slab over a crust on solar aspects and surface hoar on North aspects remains a concern.

Avalanche Summary

Yesterday cooler temps and cloud cover resulted in a smaller cycle than previous days producing only several loose wet avalanches up to size 2 on solar aspects and low elevation North aspects.

Confidence

Problems

Loose Wet

Unsettled weather may bring periods of rain. Temps remained above freezing overnight preventing an overnight recovery. If rain amounts are higher than forecast they may trigger loose wet avalanches. The moist surface may be easily triggered by skiers

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

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. Natural avalanches continue to observed on these layers.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Apr 24th, 2015 8:00AM