Avalanche Forecast

Issued: Nov 20th, 2015 7:21AM

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

esharp, Avalanche Canada

South Columbia.

Given the very limited information on hand for this bulletin, I would tread cautiously this weekend and take the time to gather snowpack information as I go. As always, we would love for you to submit any observations from your day to the MIN.

Summary

Confidence

Fair - Due to the number and quality of field observations

Weather Forecast

Freezing levels could rise as high as 1200m over the weekend with a temperature inversion developing overnight on Saturday. A cooling trend is expected with the arrival of the next storm system on Monday when up to 15cm of snow is possible Winds will be mainly light to moderate from the west throughout the forecast period.

Avalanche Summary

The storm earlier in the week resulted in a widespread avalanche cycle that produced some large avalanches.

Snowpack Summary

Up to 50cm of low density snow fell in the storm earlier this week. Over the last couple of days moderate westerly wind is likely to have formed pockets of windslab on east and northeast east aspects.Below this were dealing with a complex snowpack. A couple of layers of surface hoar were formed earlier in the month. Where they exist, they are likely to be found buried down 80 to 120 cm. Depending on where you dig, you might also find on or more crusts. It would be wise to test these layers before committing to a slope. Facets can be found at the bottom of the snowpack at higher elevations in the alpine, especially on northerly aspects.Remember that its still a thin snowpack. Rocks and stumps may be lurking unseen just below the surface. Ride with care!

Problems

Wind Slabs

Westerly wind will have redistributed the low density storm snow from earlier in the week, forming soft windslabs. I suspect that the snow in lee features will be quite reactive. Look for shooting cracks as a sign you are entering a wind loaded area.

Be careful with wind loaded pockets>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Persistent Slabs

A variety of buried persistent weak layers have been reported from across the region including surface hoar and crusts. Although it is starting to look like winter at upper elevations we're still dealing with a highly variable early snowpack.

Early season hazards such as rocks, trees and stumps are lurking on or just under the surface>Now is a good time to dig a snow profile (or two) and figure out how the snowpack changes with aspect and elevation.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 4

Valid until: Nov 21st, 2015 2:00PM