Avalanche Forecast

Issued: Dec 27th, 2015 3:00PM

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

Alberta Parks matt.mueller, Alberta Parks

The holy trinity of low hazard, no wind and good riding everywhere is gone. Thin wind slabs are lurking around in the alpine - watch the big fans under head walls and moraine features. Terrain unmolested by the wind should still be good riding . [PJ]

Summary

Confidence

High - Due to the number of field observations

Weather Forecast

Some light snow (5mm) forecast for Monday. Winds will be light and variable in the alpine. Freezing levels will be in the valley bottom for the next 3-4 days.

Avalanche Summary

A small avalanche cycle, up to size 1.5 was observed today along the Smith Dorrian/Spray HWY as a result of the winds yesterday and through the evening. These were predominantly thin, 10-20 cm wind slabs and most of them were on north, northeast and east aspects directly below large alpine head walls. These small slab avalanches were observed between 2400-2600 meters. Some cross-loading did occur as well but no natural avalanches were produced from the influence of the winds on these features.

Snowpack Summary

The winds have finally come back to K-Country. 5-10cm hard slabs have formed in exposed alpine features overnight. The snowpack from TL and below is losing its strength and structure due to faceting from cold temps. Below 1900 meters, the snowpack is rotten to the ground and exhibiting more normal characteristics. Above 1900 meters the snowpack is supportive but the upper snowpack is also losing strength.  Cornices continue to develop.

Problems

Wind Slabs

An icon showing Wind Slabs
Breakable wind slabs, 10-20 cm have formed up on north through east facing alpine fans in the immediate lee of big alpine walls due to moderate-strong winds from the south west.
Be careful with wind loaded pockets while approaching and climbing ice routes.>Avoid cross loaded features.>

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Dec 28th, 2015 2:00PM