Avalanche Forecast

Issued: Apr 29th, 2015 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 Storm Slabs, Cornices and Loose Wet.

tim mcallister, Parks Canada

Jasper.

Up to 30cm of new snow up high (above 2100m) around the forecast region, forming a touchy storm slab on lee aspects. Winter is temporarily back in the mountains.

Summary

Weather Forecast

Weather models tend to agree that we are in for more of the same wet and cool weather for the next several days. Snow will continue to fall in the alpine and whipped around by moderate winds from the west.

Snowpack Summary

Up to 30 cm of new snow in the alpine today is sitting on a supportive melt-freeze crust/mid-pack. Uncertain how well it is bonding to crusts. Deep weak layers dormant when temperatures are below freezing but may be triggered as temperatures rise and increased load.Â Snowpack is weak below tree line and isothermal in many locations.

Avalanche Summary

Widespread storm slabs forming in the alpine with this new dump of snow. Numerous loose wet avalanches expected with rain at tree line and below,

Confidence

Problems

Storm Slabs

Storm slabs on lee aspects in the alpine will be touchy as they are sitting on harder surfaces.

Avoid lee and cross-loaded terrain near ridge crests.Use caution in lee areas in the alpine and treeline. Recent storm snow has formed touchy slabs.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 3

Cornices

Give cornices a wide berth when travelling on or below ridges.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Loose Wet

Natural loose wet activity expected during the heat of the day, particularly on steep solar aspects.

Start and finish early before the surface crusts melt.

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

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Apr 30th, 2015 4:00PM