Avalanche Forecast

Issued: Feb 7th, 2019 4:37PM

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

mbender, Avalanche Canada

South Columbia.

There is potential for triggering large avalanches treeline and below due to the presence of a persistent slab problem. Click here to see our Forecasters' Blog for a more detailed description of current conditions.

Summary

Confidence

High - The weather pattern is stable

Weather Forecast

FRIDAY - Mainly cloudy with isolated flurries / Light east wind / alpine temperature -18SATURDAY - Mainly sunny / light to moderate east wind / alpine high temperature near -19SUNDAY - Mix of sun and cloud / light northeast wind / alpine temperature -15

Avalanche Summary

A persistent weak layer that was buried in mid January continues to be reactive to human triggers. This layer is sensitive enough for avalanches to trigger remotely (from a distance). Human triggered avalanches up to size 2.5 were reported on Sunday, Monday, Tuesday and Wednesday on a variety of aspects treeline and below. There have also been a few reports of natural and skier triggered windslab avalanches in the alpine size 1-2 in the past 3 days.

Snowpack Summary

20-70 cm of recent new snow sits on wind slab, surface hoar (feathery crystals), facets (sugary snow) and a crust on sun-exposed slopes. In many areas, recent winds have formed wind slabs on all aspects due to shifting wind directions. The most notable feature in the snowpack at this time is a persistent weak layer that was buried in mid January, which is now buried 40-90cm. This layer consists primarily of surface hoar, however there is also a crust associated with it on sun-exposed slopes. This layer is the most prominent at treeline and below, and continues to produce avalanches.

Problems

Persistent Slabs

40-90 cm of snow sits above a weak layer of surface hoar (feathery crystals) and crust. This layer continues to be reactive to human triggers.

Any steep opening in the trees should be treated as suspect right now.Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible

Expected Size

1.5 - 3

Wind Slabs

20-70 cm of recent snow has been redistributed by north and east winds.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.If triggered, wind slabs may step down to deeper layers and result in even larger avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Feb 8th, 2019 2:00PM