Avalanche Forecast

Issued: Feb 21st, 2014 4:00PM

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

garth lemke, Parks Canada

Jasper.

Human triggered avalanches remain possible on specific slopes such as steep convex shaped wind-loaded features. Skiing is good alpine to treeline locations where sheltered from the wind.

Summary

Weather Forecast

A dusting of snow Friday into Saturday with light North winds on Saturday and cold overnight temperatures. Sunday into Wednesday will be sun and cold overnight temperatures with daytime warming in the afternoons.Â

Snowpack Summary

There is about 30cm overtop a facet and decomposing surface hoar layer from the previous cold weather. This seems to be most prevalent from treeline into the lower alpine elevations. Below tree line there is a supportive yet shallow mid-pack over facets. Alpine has a variety of layers in top 1m but generally all well bridged.

Avalanche Summary

No new natural avalanches were observed or reported.

Confidence

Problems

Persistent Slabs

This persistent weak layer consists of facets and decomposing surface hoar under 30cm of surface snow. It sits on a mixture of crusts and firm snow. It is of most concern at treeline and subalpine zones between 2000-2400m.

Assess start zones carefully and use safe travel techniques.Caution around convexities or areas with a thin or variable snowpack.

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

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Wind Slabs

Where ever the wind has buffed the surface into a slab should be carefully evaluated particularly ridgetop transitions. Pockets of slab have also been created by valley bottom winds and have been found in exposed locations at treeline and below.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Feb 22nd, 2014 4:00PM