Avalanche Forecast

Issued: Feb 16th, 2016 4:00PM

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

Max Darrah, Parks Canada

Jasper.

Public reports of new wind slab avalanches at treeline coincide with Visitor Safety field work today which found touchy new windslabs in crossloaded terrain. Use caution as you transition into wind affected areas.

Summary

Weather Forecast

5cm of snow arriving for the Icefields Parkway with freezing levels rising to1800m on Wednesday. Alpine high of -6C tomorrow with flurries and SW winds, 20km/hr gusting to 50km/hr. Another pulse arriving Thursday bringing 5-10cm, high winds and freezing levels to 2000m.

Snowpack Summary

5-10cm of snow in past 72 hours being distributed by mod-strong SW winds. New wind slab forming in areas where snow available for transport. Solar aspects have a breakable crust 10cm thick. Mid-pack consists of buried wind and persistent slab, which lay on a bed of basal facets. Decomposing surface hoar ~40cm down in isolated areas at treeline.

Avalanche Summary

Field team in the Whistler Creek drainage reported isolated large avalanches to size 3 in the alpine from past 72 hours and remotely triggered 2 small avalanches in wind loaded terrain at treeline. These small avalanches are noteworthy because of the remote triggering, the significant propagation and slab thickness that ranged from 20cm to 1m.

Confidence

Problems

Persistent Slabs

Previously formed slabs now comprise the upper and mid-pack in many locations. Natural and human triggered avalanches are possible.

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Wind Slabs

Strong winds have redistributed storm snow and wind slab can be found at all elevations. Caution on cross loaded gullies and lee aspects.

Use caution in lee areas. Recent wind loading has created wind slabs.Caution in lee and cross-loaded terrain near ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Feb 17th, 2016 4:00PM