Avalanche Forecast

Issued: Dec 16th, 2019 5:00PM

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

Avalanche Canada cgarritty, Avalanche Canada

Two persistent weak layers are at play in the region - but neither of them are giving consistent feedback. A tricky situation! Avoid overthinking the problem and instead seek out lower angle terrain while maintaining diligent travel practices.

Summary

Confidence

High -

Weather Forecast

MONDAY NIGHT: Cloudy with isolated flurries and a trace to 5 cm of new snow. Moderate southwest winds.

TUESDAY: A mix of sun and cloud with isolated flurries and a trace of new snow. Strong southwest winds. Alpine high temperatures around -6

WEDNESDAY: Mainly cloudy. Light to moderate south winds. Alpine high temperatures around -6.

THURSDAY: Cloudy with isolated flurries and a trace of new snow, increasing overnight. Light to moderate southwest winds. Alpine high temperatures around -5.

Avalanche Summary

There were reports of a size 1 human triggered avalanche, and natural size 2 avalanche on Saturday that released on the persistent weak layer that is down about 50-60 cm

There were a few reports of explosives triggered storm slab avalanches up to size 2 on Friday.

There were a few human and explosives triggered storm slab avalanches size 1-2 reported on Thursday.

Check out this MIN report of an avalanche in the Big White backcountry on Thursday.

Snowpack Summary

15-30 cm of recent snow sits on a weak layer of feathery surface hoar in many sheltered areas, and on a crust on steep south facing slopes. This layer may be reactive to human triggers, especially where wind loading has formed a deeper slab above it.

There is also a persistent weak layer down approximately 60-100 cm that mainly consists of a crust with sugary faceted snow on top of it. This layer is more likely to be reactive to human triggers in shallow, rocky areas.

Problems

Persistent Slabs

An icon showing Persistent Slabs

There are two prominent weak layers in the snowpack right now that are of concern. The first is a layer of surface hoar that was buried last week, and is approximately 20-30 cm deep. The second is a persistent weak layer that is now buried 50-60 cm. Both layers could potentially be reactive to human triggers. Be aware that if the shallower layer is triggered, it may step down to the deeper layer, resulting in a large avalanche.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Dec 17th, 2019 3:30PM