Avalanche Forecast

Issued: Jan 9th, 2014 4:34PM

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

steve blagbrough, Parks Canada

Jasper.

Summary

Weather Forecast

A forecast of snow flurries and light winds should do little to change the avalanche hazard in the next 24 hours.

Snowpack Summary

Last weekend's storm snow overlies older wind slabs. In the alpine this newer snow has itself be blown into storm slabs which shear with easy to moderate force. The base of the snowpack is weak and unstable at all elevations. Near treeline the midpack is supportive and untracked powder can be found in wind sheltered locations.

Avalanche Summary

Increased loading with new snow and wind forecast for the weekend will renew avalanche activity at treeline and above. Field team noted the debris of 2 sz 2.5 slab avalanches which had released in the last 24 hours on the basal facets at alpine elevations. Control work with large explosives only produced small slides below treeline today.

Confidence

Intensity of incoming weather systems is uncertain on Saturday

Problems

Deep Persistent Slabs

Many avalanche paths have already slid in the 2,400 m - 2,800 m range. Slopes that have not failed are expected to fail with the increased snow loading and winds this weekend.

Be aware of thin areas that may propogate to deeper instabilites.Avoid steep, open slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Wind Slabs

The upper snowpack is a stratified layer of multiple windslabs. Recent field tests have produced failures with moderate shear strength. Currently this condition is less prevalent at treeline. Forecasted snowfall and wind will increase this concern.

Avoid ice climbs that are in terrain traps below large start zones.Avoid freshly wind loaded features.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 10th, 2014 4:00PM