Avalanche Forecast

Issued: Mar 9th, 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.

Considering the forecast, we recommend avoiding accessing Maligne Lake, Whistler and Portal Creeks Thursday and into the weekend to allow the region to stabilize with the new load.

Summary

Weather Forecast

Forecasted south wind and snow, up to 10cms overnight and continued snowfall over the day with total forecasted amounts to near 30cms. As the storm progresses the winds are expecting to increase from moderate to strong values. Temperatures to remain cool but freezing levels up to 2000ms in the Icefields.

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

Field teams in the Maligne/Bald Hills with good visibility. Large destructive avalanches noted in the area up to size 3, one measuring 900ms in length at the crown. Potential for human triggered is very likely. Not expected to get any better with new forecasted storm snow. No reports of any significant avalanche activity in the Icefields area.

Confidence

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

Problems

Persistent Slabs

This problem is very active in the Maligne and surrounding Jasper area with remotely triggered avalanches being 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 all avalanche terrain during periods of heavy loading from new snow, wind, or rain.

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. Bonding should be good but progress cautiously into steeper terrain.

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

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 10th, 2016 4:00PM