Avalanche Forecast

Issued: Jan 23rd, 2013 4:00PM

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

Grant Statham, Parks Canada

Jasper.

A few centimeters of snow are expected overnight. If this occurs, hopefully this will soften up the skiing, and if so perhaps a few isolated, small soft slabs (10-15) might form in windloaded areas.

Summary

Weather Forecast

The ridge of high pressure that has dominated the pattern for the last week is being pushed out of the area by a southwesterly flow. A cold front will cross the Jasper area on Wed night leaving a maximum of 5 cm of snow. Thursday will see broken skies, no precipitation, moderate NW winds, and alpine temperatures ranging from -5 to -10.

Snowpack Summary

No significant changes to the snowpack in the last 24-hours. Widespread wind effect in most exposed areas at and above treeline has created hard slabs which overlie a weakness of facets or surface hoar down 10-40 cm (depending on location). Tests indicate a shear on this layer, but triggering is unlikely due to the stiffness of the slab.

Avalanche Summary

No new avalanches were observed along the Maligne Lake road today.

Confidence

Problems

Wind Slabs

Recent wind effect has destroyed most of the surface snow and left hard slabs which could be triggered from shallow snowpack areas, or in isolated steep pockets of windloaded snow.

Be careful with wind loaded pockets

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1 - 3

Deep Persistent Slabs

The lower depths of the snowpack are slowly facetting and becoming weaker, especially in shallow areas. Choose the deeper snowpack areas for your travel.

Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Jan 24th, 2013 4:00PM