Avalanche Forecast

Issued: Dec 25th, 2017 8:00AM

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

mark herbison, Parks Canada

Glacier.

Cold temps and light winds have preserved the excellent snow quality.Assess the snowpack before entering your line.Happy Holidays!

Summary

Weather Forecast

A strong ridge of high pressure is sitting over the region giving us clear sunny skies. The winds will be 5-20km/hr from the North, with an Alpine high of -18... bbrrr thats cold, bring an extra layer or two and stay in the sun! The ridge of high pressure looks like it will persist until mid week, with no snow in the forecast until Friday.

Snowpack Summary

Cold temps are promoting surface faceting. Below tree line the top 40cm of the snowpack is unconsolidated and sits on the Dec 15 surface hoar which is widespread and largest where sheltered. In the alpine, Dec 15 is a thin crust on solar aspects and small surface hoar on polar aspects. Pockets of wind slab exist in the alpine and at tree line.

Avalanche Summary

No new avalanches observed yesterday.Numerous natural avalanches from a few days ago up to sz 2.5 in steep terrain.

Confidence

The weather pattern is stable

Problems

Persistent Slabs

40-50cm of snow is settling into a persistent slab which sits on the Dec 15 surface hoar. Expect the slab to be more reactive as you transition into steep and/or wind effected terrain. Solar aspects have a thin crust layer below the slab.

Be aware of the potential for large avalanches due to the presence of buried surface hoar.Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Wind Slabs

Recent variable winds formed pockets of wind slab in the alpine and exposed areas at tree line on all aspects. These slabs may have surface hoar or crust underneath, leading them to be sensitive to human triggering.

Watch for shooting cracks or stiffer feeling snow. Avoid areas that appear wind loaded.Variable winds have created pockets of wind slab on all aspects.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Dec 26th, 2017 8:00AM