Avalanche Forecast

Issued: Apr 6th, 2013 8:13AM

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

catherine brown, Parks Canada

Glacier.

Spring conditions are present in the park. Keep your heads up to hazards like cornices, glide cracks, open creeks and loose wet avalanches.

Summary

Weather Forecast

Temperatures will cool down today with light, possibly moderate precipitation in the forecast. Freezing levels will remain around 1800 m. Winds will be moderate from the west/southwest. Conditions dry out on Sunday and temperatures are forecast to remain near seasonal. Light convective precipitation will arrive on Monday.

Snowpack Summary

Warm temperatures and moist snow/rain overnight did not allow for a good freeze. An isothermal snowpack has been reported in some locations at treeline. These conditions result in a loose, unconsolidated snowpack. Precipitation that did fall as snow over the last few days will be heavy and wet.

Avalanche Summary

Artillery avalanche control along the highway corridor yesterday produced numerous size 2-2.5 loose, moist avalanches. Most of these avalanches stopped mid-path.With poor visibility being a factor, we observed a few natural avalanches yesterday, from size 2-3. In the past week many recent glide crack avalanches have released.

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Problems

Loose Wet

Natural avalanches are possible with the current spring conditions. Avalanches that trigger on a shallow crust can dig deeper into the isothermal snow and get bigger.

Minimize exposure during periods of heavy loading from new snow, wind.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Storm Slabs

Up to 15 cm of new snow at treeline and above could be rider triggered. Watch for this snow to have formed a slab of denser snow. Especially on leeward features in open terrain.

Avoid freshly wind loaded features.Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Apr 7th, 2013 8:00AM