Avalanche Forecast

Issued: Jan 14th, 2014 4:00PM

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

mike eder, Parks Canada

Jasper.

Redistributed storm snow has added weight to windslabs on lee aspects and terrain features. Be cautious of thin areas near ridgecrests.

Summary

Weather Forecast

Temperatures are expected to remain relatively warm and will rise above zero in the valley bottoms by Thursday. Some rain may fall near valley bottom. Warm temperatures are expected to stay through the night on Friday. Light accumulations may be in isolated areas in the forecast area as it remains cloudy with sunny periods into the weekend.

Snowpack Summary

Up to 70cm of storm snow has been redistributed by moderate to strong SW winds creating wind slab over a strong mid-pack in lee features on top of a weak basal facets layer at the ground. Warmer temperatures are contributing to settlement in the snowpack. Light flurries may add additional weight to the snowpack.

Avalanche Summary

Natural activity was observed at all elevations in the Icefields area today. The alpine had slabs up to size 2.5 on NE through to SE aspects from 2300m to 2700m. Below treeline, small slab avalanches to size 1.5 occurred on steep open slopes. Monday's field team remotely triggered a size 2.5 from a distance of 20m on a SE aspect.

Confidence

Freezing levels are uncertain on Friday

Problems

Deep Persistent Slabs

Warmer temperatures will contribute to overloading the weak basal facets leading to full depth avalanches in the valley bottoms. Be cautious of steep slopes along terrain traps such as creeks.

Be aware of thin areas that may propogate to deeper instabilites.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

As the warmer temperatures stiffen up the snow surface, even a small avalanche could step down to the basal facet layer resulting in a full depth avalanche.

Avoid ice climbs that are in terrain traps below large start zones.Avoid lee and cross-loaded terrain near ridge crests.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Jan 15th, 2014 4:00PM