Avalanche Forecast

Issued: Nov 26th, 2021 4:00PM

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

Avalanche Canada dsaly, Avalanche Canada

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Find the best riding in areas sheltered from wind. Fresh wind slabs have formed over older, more dense slabs and a variety of previously wind-affected surfaces.

Summary

Confidence

Low - Uncertainty is due to limitations in the field data.

Weather Forecast

Friday night: Cloudy with isolated flurries and starry breaks. West-southwest winds, 30-45 km/hr. Alpine temperature low -9 C. Freezing dropping to valley bottom overnight.

Saturday: Cloudy with sunny breaks and late afternoon flurries. Southwest winds, 35-55 km/hr. Alpine temperature high -3 C. Freezing level 1500 m and rising into the evening.

Sunday: Wet flurries and rain, 10-40 mm. Southwest winds, 40-60 gusting to 90 km/hr. Alpine temperature high +3 C. Freezing level rising above 2000 m.

Monday: Mostly cloudy, isolated flurries, and sunny breaks, 5-10. Southwest winds 20-30 km/hr. Alpine temperature high 0 C. Freezing level 2000 m and dropping.

Avalanche Summary

On Thursday, forecasters in neighboring Kananaskis Country reported a size 1.5 wind slab avalanche which failed naturally on a NW aspect around 2200 m. Although outside the South Rockies, we have a similar snowpack in our region and may see similar avalanche characteristics.

Snowpack Summary

Wind is impacting 5-20 cm of recent snowfall, fresh wind slabs have formed over a variety of previously wind-affected surfaces. Expect to find anything from bare rock to dense wind slab along ridgelines and in open terrain.

Two crusts are found in the snowpack: the mid-November rain crust buried 20-30 cm and reported up to 2100 m, and a crust from early November found at the bottom of the snowpack up to 2300 m, this crust is being to break down and facet.

Snowpack depths range from 40-150 cm at treeline elevations. Higher elevations may hold a deeper snowpack, but also be more heavily impacted from recent winds. Snowpack depths decrease rapidly below 1900 m.

Early season hazards are very real right now, be wary of thin/shallow snowpacks, rocks, stumps, creeks, and other sharks hidden under fresh snow.

Terrain and Travel

  • Be alert to conditions that change with elevation and wind exposure.
  • Approach lee and cross-loaded slopes with caution.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind will continue to impact any loose snow, building new wind slabs over an already wind-affected snowpack. The most reactive areas will likely be around ridges and open terrain at treeline and above. Be ready for a variety of wind-affected surfaces varying from fresh wind slabs, older and more dense slabs, to scoured and polished rock.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Valid until: Nov 27th, 2021 4:00PM