Avalanche Forecast

Issued: Jan 31st, 2017 4:36PM

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

Avalanche Canada jlammers, Avalanche Canada

The load over the deep persistent slab problem in parts of the region has reached a critical level. Triggering a full depth of snowpack avalanche is possible. For more details, click here for the latest Forecaster Blog post.

Summary

Confidence

Moderate -

Weather Forecast

Clear skies are expected for Wednesday and Thursday with increased cloud forecast for Friday. Ridgetop winds should remain generally light to moderate from the east for Wednesday and Thursday, and then become stronger on Friday. Freezing levels should remain at valley bottom for the forecast period.

Avalanche Summary

On Sunday there were several skier, snowmobile and naturally triggered avalanches to report from riding areas to the west of Smithers. One of these avalanches in the Microwave area involved the full depth of the snowpack and resulted in a full burial. Click here for a description and images of the incident on Facebook. It is well worth a read. Another report in the Ashman area shows a skier-triggered size 2 avalanche running on surface hoar at the storm snow and old snow interface in a sheltered area at tree line. Natural avalanches are reported to be full depth of the snowpack to size 3.5 in the alpine and at tree line.

Snowpack Summary

A series of snowfalls last week accumulated 40-80 cm of storm snow, which now sits above a widespread rain crust up to about 1300 m. At tree line and above, the storm snow is settling and/or being redistributed into new wind slabs. Below, several buried surface hoar layers can be found, between 50-100 cm deep. Before the storm, 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 sitting on top has reached a critical level and has woken-up a deep persistent slab problem in many parts of the region. The consequences of triggering an avalanche on this layer are high. This is a good time to be very cautious and disciplined with terrain choices.

Problems

Deep Persistent Slabs

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

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Storm Slabs

An icon showing Storm Slabs
New snow and strong winds have formed storm and wind slabs. Conditions will be especially touchy in wind-exposed areas. Surface avalanches may also step down to deeper, more destructive layers.
Be cautious as you transition into wind affected terrain.If triggered the storm slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Feb 1st, 2017 2:00PM

Login