Avalanche Forecast

Issued: Feb 15th, 2013 4:00PM

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

steve blake, Parks Canada

Jasper.

We may see 20cm of new snow on Saturday night. If we do, expect to see the avalanche danger increase.

Summary

Weather Forecast

Cooler temperatures and some new snow is expected for Saturday afternoon and evening.

Snowpack Summary

Hard wind slab is bridging the weak basal facets above treeline.Â Limited whumpfing has been observed at treeline in the Parker Ridge area.Â Very little new snow in the past few days.Â Moderate SW winds continues to build pockets of thin windslab on lee aspects at treeline and above. The snowpack is weak and faceted below treeline.

Avalanche Summary

On Wednesday, several loose snow avalanches were observed along SE facing alpine ridge lines.

Confidence

Intensity of incoming weather systems is uncertain on Saturday

Problems

Wind Slabs

Wind and little new snow dominate the alpine landscape. On certain lee features this crust is thick enough to form a wind slab, and it may be possible to trigger an avalanche on steep unsupported terrain from thin snowpack areas.

Avoid convexities or areas with a thin or variable snowpack.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

The snowpack in the alpine and at tree line consists of multiple wind laminated layers. How the terrain has influenced the formation and character of these layers on a given slope is the main question to keep in mind while traveling.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1 - 3

Valid until: Feb 16th, 2013 4:00PM