Avalanche Forecast

Issued: Nov 12th, 2021 4:00PM

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

Ross Campbell,

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The avalanche hazard will rise considerably over the next few days with the incoming storm! Early season hazards may be hiding just below the snow surface, where even a small avalanche could have severe consequences.

Summary

Weather Forecast

Saturday will be mainly cloudy with flurries, freezing levels could reach 1200m, with moderate to strong SW winds. A significant storm is forecasted on Sunday and Monday! On Sunday we could see ~40cm of new snow, warming temperatures and strong to extreme winds from the SW. Monday will be a similar day to Sunday but with slightly less new snow.

Snowpack Summary

Recent strong winds, new snow and warming temperatures has deposited fresh storm slabs in the Alpine and exposed areas of TL. Height of snow varies significantly with elevation from ~30cm @ Rogers Pass to ~175cm in the Alpine. There are 2 prominent crusts to date, the Nov 5th buried ~40cm and the October crust lies near the base of the snowpack.

Avalanche Summary

Natural activity increased today (Friday) in the HWY corridor, and there are several MIN reports about the Cheops North paths. Avalanche activity will peak on Sun and Mon as Rogers Pass gets hammered by the next storm. Human triggered avalanches will be likely on Saturday in the Alpine and exposed areas of TL in steep unsupported terrain features.

Confidence

Due to the number of field observations

Problems

Storm Slabs

An icon showing Storm Slabs

10-20cms of new snow, strong wind, and warming temperatures has created storm slabs in the Alpine and exposed areas of Treeline on specific terrain features. Expect storm slabs size and distribution to increase considerably on Sunday and Monday!

  • Early season hazards such as rocks, trees and stumps are very prevalent
  • Use caution in lee and cross-loaded terrain near ridge crests.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Nov 13th, 2021 4:00PM