Avalanche Forecast

Issued: Feb 5th, 2017 3:54PM

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

mgrist, Avalanche Canada

Northwest Inland.

Wind slabs are a significant concern in the alpine. The probability of triggering a full depth avalanche has lowered but the consequence of doing so remains High. Click here for more information in our blog on this specific problem.

Summary

Confidence

Moderate - The weather pattern is stable

Weather Forecast

Steady weather pattern for the Northwest: Cold and mostly clear with no precipitation.MONDAY: Mix of sun and cloud / Light to moderate east wind / Alpine temperature -22TUESDAY: Sunny / Light southeast wind / Alpine temperature -14 WEDNESDAY: Sunny / Moderate east wind / Alpine temperature -15

Avalanche Summary

On Saturday, slab avalanches were reported in the Shootout area of Telkwa range. A remote-triggered Size 2 wind slab was set off by a skier in the Kispiox on Friday, running on basal facets. There have been few avalanches reported over the last 3 days. However, it is still possible to trigger an avalanche on deeper weak layers at upper elevations either from a thin spot or a smaller avalanche stepping down.

Snowpack Summary

Last weekend's snowfall sits on a rain crust up to about 1400 m in many parts of the region. At tree line and above, the storm snow is settling and/or being redistributed into new wind slabs, especially on west through southeast aspects. Below, several buried surface hoar layers can be found, between 30-70 cm deep. Reports from last week indicate these layers had been yielding moderate to hard results in snowpack tests. A generally stiff mid pack sits above weak sugary snow near the ground. The new load from last week reached a critical level and woke up a deep persistent slab problem in many parts of the region, especially shallower (100-140cm) snowpack areas. Currently the probability of triggering an avalanche on those deeper layers has lowered but the consequence remains high. It is still a good time to be cautious and disciplined with terrain choices at upper elevations.

Problems

Wind Slabs

Moderate to strong winds have formed wind slabs in lee areas. Surface avalanches may also step down to deeper, more destructive layers.

Be cautious as you transition into wind affected terrain.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

Last week's snow and wind have added a critical load to weak, sugary snow at the base of the snowpack and potential exists for full depth avalanches. This problem may be more acute in lower snowpack areas.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.Be aware of the potential for full depth avalanches due to weak layers at the base of the snowpack.Avoid steep convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Feb 6th, 2017 2:00PM