Avalanche Forecast

Issued: Mar 10th, 2016 4:00PM

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

deryl kelly, Parks Canada

Jasper.

The persistent slab problem is widespread and will likely trigger where the snowpack is shallow. Snowpack is deeper in the Icefields, but if you trigger it, the result is deeper and more destructive avalanches.Good riding found BTL in Parkers.

Summary

Weather Forecast

Forecasted snowfall amounts delayed and most intense precip observed in the later afternoon and expected to continue through the night expecting more then 10cms. Strong south winds are expecting to continue, decreasing over the day Friday. Temperatures to remain cool but freezing levels up to 2000ms in the Icefields. Broken skies in the pm.

Snowpack Summary

Maligne/Jasper: Variable snow depth above tree-line, relative to exposure. Average HS 70cm. Surface wind slabs and persistent slab down 40-90cm, very touchy, even on low angle slopes.Icefields: Variable snow depth above tree-line, relative to exposure. Average HS 120cm. Cornices and building wind slabs overlaying supportive mid pack and weak base.

Avalanche Summary

Previously noted large destructive avalanches noted in the Maligne Valley up to size 3, one measuring 900ms in length at the crown. Field team in the Icefields noted 3 avalanches on similar cross-loaded Alpine features, up to size 2.5 on south aspect. No other Alpine observations due to weather.

Confidence

Intensity of incoming weather systems is uncertain on Thursday

Problems

Persistent Slabs

This problem is most active in the Maligne and surrounding Jasper area where the average snow pack is shallow. Remotely triggered avalanches reported on very low angle terrain. This problem is proving much less active in the Icefields area.

Remote triggering is a concern, watch out for adjacent slopes.Avoid shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 3

Wind Slabs

Expect slab development immediate to lee ridge lines and cross loaded features.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 11th, 2016 4:00PM