Avalanche Forecast

Issued: Jan 17th, 2017 4:32PM

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

Avalanche Canada mbender, Avalanche Canada

There is a lot of uncertainty surrounding the intensity of precipitation amounts in the region. Certainly if the freezing level rises in combination with the potential for heavy snowfall and strong winds, the avalanche danger will be elevated.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Wednesday

Weather Forecast

WEDNESDAY: Snow with 25-40cm of accumulation and rain possible at lower elevations, moderate to strong southwest winds, freezing level around 1300m.THURSDAY: Flurries, accumulations 5-10cm, strong southwest winds, freezing level around 1300m.FRIDAY: Mainly cloudy with the possibility of isolated flurries, light south wind and freezing level around 1000m.More details can be found on the Mountain Weather Forecast.

Avalanche Summary

Conditions are expected to change overnight as a storm moves into the region and new storm slabs develop. As the load increases over the next few days expect the likelihood of deeper buried layers failing to increase under the new load of snow combined with wind and warm temperatures.

Snowpack Summary

A storm is arriving overnight Tuesday and expected to intensify during the day on Wednesday. Expect new storm slabs to develop above existing weak layers described here. Recent cold and clear weather has promoted both faceting of surface snow as well as the growth of surface hoar that has been reported to be up to 15mm in size below treeline. A sun crust has also been reported forming on steep solar aspects. Beneath a variety of old snow surfaces are buried, including wind scoured surfaces and old wind slabs, widespread near surface faceting (sugary snow), surface hoar in sheltered locations, and/or a breakable sun crust on steep solar aspects. The mid-December surface hoar/ facet layer typically sits down 40-70 cm. This layer is still reactive to some snowpack tests in some areas but is currently considered to be dormant or inactive. However, once the snowpack starts to see a big change, like warming, the likelihood of triggering may increase.

Problems

Storm Slabs

An icon showing Storm Slabs
Forecast new storm snow combined with strong southwest winds and warming temperatures are expected to increase the likelihood of avalanche activity.
Watch for signs of instability such as whumpfing, or cracking. The new snow will require several days to settle and stabilize.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Jan 18th, 2017 2:00PM