Avalanche Forecast

Issued: Nov 25th, 2019 3:00PM

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

Avalanche Canada cgarritty, Avalanche Canada

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A shift to easterly outflow winds is likely to gradually expand our wind slab problem to all aspects. Avalanche danger will be CONSIDERABLE if strong winds arrive before the end of the day.

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

Monday night: Mainly cloudy with isolated flurries and a trace of new snow. Light northwest winds.

Tuesday: Mainly cloudy. Light to moderate east winds, increasing over the day. Alpine high temperatures around -11.

Wednesday: Mainly sunny. Moderate to strong northeast winds. Alpine high temperatures around -16.

Thursday: Sunny. Moderate variable winds, easing over the day. Alpine high temperatures around -10.

Avalanche Summary

No new avalanches have yet been reported in the region, but it's safe to assume Saturday's storm caused natural avalanche activity at higher elevations.

For the early part of this week, the focus remains on the new snow, particularly in areas where winds may have blown it into deep and reactive wind slabs.

Concern is reduced in areas where the new snow wasn't quite able to overcome the depth of ground roughness.

Snowpack Summary

25 to 30 cm of new snow accumulated in the region over the course of Saturday's storm. Observations in the region are limited, but we have indications that for most areas where previous snow cover existed, the new snow buried a supportive melt-freeze crust.

Given the lack of recent snowpack observations, the new snow's bond with the old surface remains in question.

Total snow depths are likely approaching 50-70 cm at alpine elevations in the Smithers area, with depths diminishing rapidly with elevation below 1500 metres.

Problems

Wind Slabs

An icon showing Wind Slabs

A shift to strengthening easterly winds on Tuesday means that wind slabs could be found on a wide range of aspects by the end of the day. This problem will likely be most pronounced at higher, more wind-exposed elevations. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Nov 26th, 2019 5:00PM