Avalanche Forecast

Issued: Apr 25th, 2016 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, Wet Slabs and Storm Slabs.

tim haggarty, Parks Canada

Banff Yoho Kootenay.

We have finished producing daily forecasts for the year. Enjoy the SPRING CONDITIONS. Stay up to date on mountain conditions with Parks Mountain Safety and the ACMG's Mountain Condition Report.

Summary

Weather Forecast

The snowpack's strength is tied mainly to heating at this time of the year. Pay attention to freezing levels as well as heat inputs from rain and the sun to help determine the strength of surface crusts and the condition of the underlying snow.

Snowpack Summary

Approaches are becoming difficult as the snowpack below treeline is melting away quickly and is generally isothermal. In the high Alpine, new snow will be accumulating above recent hard surfaces.

Avalanche Summary

Loose wet and wet slab avalanche activity has been reported as a result of recent warm temperatures and precipitation.

Confidence

Problems

Loose Wet

At low elevations a crust may be found over wet isothermal snow following an overnight freeze. All avalanche terrain should be avoided later in the day when the crust on top of the snowpack breaks down due to daytime heating.

Travel early on frozen crusts before the heat of the day.Watch for clues, like sluffing off of cliffs, that the snowpack is warming up.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Wet Slabs

Wet slab activity failing on the mid and lower pack weakness remains a possibility when heating is significant enough to affect more than just the surface of the snowpack.

Pay attention to overhead hazards like cornices which could easily trigger deep slabs.If triggered the loose wet sluffs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Storm Slabs

Watch for loose dry and slab activity following spring storms that deposit snow at upper elevations.

Minimize exposure during periods of heavy loading from new snow, wind.New snow will require several days to settle and stabilize.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 26th, 2016 4:00PM