Avalanche Forecast

Issued: Feb 20th, 2023 4:00PM

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

Avalanche Canada mbender, Avalanche Canada

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Updated on Tuesday at 6:10 AM. 15 to 20 cm of snow fell overnight creating dangerous avalanche conditions at treeline and alpine elevations.

Summary

Confidence

Moderate

Avalanche Summary

Most recent avalanche activity was reported as size 1-1.5 wind slabs in the alpine.

With heavy snowfall forecast for Monday night combined with strong winds, expect there to be an increase in natural avalanche activity in the alpine and treeline.

Please continue to post your reports and photos to the Mountain Information Network.

Snowpack Summary

20-40 cm of new snow from the beginning of the week is being redistributed by primarily southwest winds.

A melt-freeze crust formed in mid-January is now buried up to 80-120 cm deep. In some areas, small facets are still found above the crust. This layer appears to be gaining strength but still remains a concern. The snow below this layer is well consolidated.

Snowpack depths are just below seasonal averages. Total amounts range from 150 to 300 cm at treeline, but decreases significantly below 1500 m.

Weather Summary

Monday Night

Cloudy with snow, accumulation 15-30cm. Wind strong southwest. Treeline temperature -5 °C. Freezing level 1300 m.

Tuesday

Mainly cloudy with flurries, accumulation 3-5cm. Wind light to moderate northwest. Treeline temperature -7 °C. Freezing level 400 m.

Wednesday

Mainly cloudy. Wind light to moderate northeast. Treeline temperature -14 °C.

Thursday

Mix of sun and cloud. Wind moderate north wind. Treeline temperature -16 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.

Problems

Storm Slabs

An icon showing Storm Slabs

Up to 30cm of new snow overnight Monday into Tuesday will form reactive storm slabs. Deepest deposits will be found in lee terrain with strong southwest winds.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A crust formed in mid-January can be found down 70 to 90 cm. In some areas facets can be found sitting on the crust.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Valid until: Feb 21st, 2023 4:00PM