Avalanche Forecast

Issued: Apr 5th, 2015 4:00PM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Loose Dry and Wind Slabs.

patrick jerome, Parks Canada

Banff Yoho Kootenay.

This spring storm dropped 10-40 cm's of low density snow. We are now at a time of the year to start thinking spring conditions. Monitor freezing levels and the strong impact of solar effect. Start early when conditions are cool and stable. PJ

Summary

Weather Forecast

Some convective flurries can expected through tonight and tomorrow and then an upper ridge will strengthen through early next week with sunny, warm and dry weather on Tuesday and Wednesday. Freezing levels will increase as the week continues up to 2000 meters and winds will remain light from the SE tomorrow.

Snowpack Summary

Storm snow amounts varied from 26cms in Lake Louise, 37 cms at Sunshine and 10 cms at Bow Summit. This low density snow did not exhibit much in the way of slab properties today. The interface with the old snow surfaces appears to be bonding well on solar aspects but on north the interface is reactive to ski cuts on terrain steeper than 30 degrees.

Avalanche Summary

Some ski cutting results by local ski areas up to size 1.5. Loose dry avalanches have also been observed naturally out of steep unsupported alpine features.

Confidence

Timing or intensity of solar radiation is uncertain on Tuesday

Problems

Loose Dry

Low density snow with little slab characteristics blankets the old interfaces and temps remain cool. The solar input on Tuesday and Wednesday could change the problem from loose dry to loose wet or wet slabs on solar aspects very quickly.

Be cautious of sluffing in steep terrain.Cornices become weak with daytime heating, so travel early on exposed slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Wind Slabs

Recent wind slabs are now buried with the forecasted up-slope storm. Monitor how these are bonding to harder surfaces below.

Use caution in lee areas. Recent wind loading have created wind slabs.The 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 6th, 2015 4:00PM