Avalanche Forecast

Issued: Nov 29th, 2022 4:00PM

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

Avalanche Canada rgoddard, Avalanche Canada

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Storm snow will be bringing with it the production of storm slabs and dangerous avalanche conditions.

Summary

Confidence

Moderate

Avalanche Summary

No new avalanches have been observed or reported in the region. Observations in our immediate area are limited at this time of year, if you head into the backcountry consider submitting a MIN report.

Snowpack Summary

Since Friday, snowfall accumulations range from 15 to 20 cm near the Duffey and upwards of 40 cm around the Coquihalla and south. At upper elevations, it covers a crust. At this writing, there has yet to be any reported reactivity on this layer. Below the crust is 40 to 80 cm of early November snow, which began covering surface roughness at upper elevations. The strength of this basal interface will become more evident with more field observations. The line where snow met dirt before Friday's snow, was around the treeline.

Terrain features poke through a building snowpack that grew from 45 to 60 cm around 1300 to 1400 m and upwards of 120 cm in the alpine. Most solar slopes and below treeline are below the threshold for avalanches.

Weather Summary

Tuesday Night

Cloudy, 15 cm accumulation, winds southeast 15 km/h gusting to 50, temperatures -5 to -10 C,

Wednesday

Cloudy with sunny periods, 10 to 15 cm accumulation, south to southwest winds 15 to 20 km/h gusting to 70, temperatures -7 C.

Thursday

A mix of sun and cloud, trace accumulation, winds north northeast 15 km/h, temperatures -10 to -15 C.

Friday

Mostly sunny, no accumulation, winds south 10 km/h, temperatures -10 to -15 C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for fresh storm slabs building throughout the day.
  • Closely monitor how the new snow is bonding to the crust.
  • Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
  • Dial back your terrain choices if you are seeing more than 30 cm of new snow.

Problems

Storm Slabs

An icon showing Storm Slabs

New snow will be sitting on a crust in many areas and it is unknown how well it will bond. This storm slab problem will be transitioning into a wind slab problem later in the day on Wednesday and into Thursday. There is a possibility of avalanches running down to lower elevations.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 1.5

Valid until: Nov 30th, 2022 4:00PM