Avalanche Forecast

Issued: Feb 3rd, 2015 4:04PM

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

steve blagbrough, Parks Canada

Jasper.

The next storm system is forecast to arrive on Thursday. Game on......again.

Summary

Weather Forecast

The next storm system arrives on Thursday. Forecast models are predicting anything from 25cm to 90cm by the end of the weekend in the Icefields area. With this precipitation amount, strong westerly winds and rising temperatures the avalanche hazard will be increasing.

Snowpack Summary

Last weeks's warm temperatures and rain resulted in a crust up to 2100m on all aspects. Higher elevations have wind affected surfaces in exposed areas and wind slabs on lee aspects. More snow has fallen in the northern part of the forecast area in the last 24 hours than in the south.

Avalanche Summary

Field team in the Icefields area today reported three size 2 and one size 2.5 slab avalanches in cross loaded features in the alpine. The size 2.5 stepped down to the November basal facet layer.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Thursday

Problems

Wind Slabs

Windslabs have developed on lee and cross loaded features at alpine elevations. The debris of four size 2 slab avalanches that initiated in cross loaded terrain in the alpine was observed by our field team in the Icefields area on Tuesday

Avoid steep lee and cross-loaded features

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

This layer remains a concern in isolated areas above treeline and may be triggered by large loads such as cornices, surface slides or from shallow areas by skiers. The entire snowpack throughout the forecast region is riding on 20cm of depth hoar.

Caution around convexities or areas with a thin or variable snowpack.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Feb 4th, 2015 4:00PM