Avalanche Forecast

Issued: Mar 24th, 2021 4:00PM

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

Avalanche Canada ahanna, Avalanche Canada

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Be aware of the potential for isolated pockets of soft wind slab in exposed alpine terrain features. Feel for changes and look for signs of instability in wind affected snow as you gain elevation. 

Summary

Confidence

Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.

Weather Forecast

Wednesday night: Flurries bringing a trace of new snow. WInds easing to light. Alpine temperatures around -7. Freezing level valley bottom.

Thursday: Mix of sun and cloud with scattered flurries. Light wind. Alpine high temperatures around -4. Freezing level 1700 m.

Friday: Mix of sun and cloud. Light to moderate westerly wind. Alpine high temperatures around -2. Freezing level 1800 m.

Saturday: Sunny. Light to moderate westerly wind. Alpine high temperatures around 0. Freezing level 2300 m.

Avalanche Summary

Explosive control work on Monday and Tuesday produced mainly size 1 loose dry avalanches and a few thin size 1-1.5 storm slabs showing minimal cohesion and propagation.

A large (size 2) glide slab occurred overnight Friday on a lower elevation slope on Mt. Fernie. It may have been coaxed into action by overnight rainfall. This serves as a great reminder to avoid slopes with glide cracks on them at all times. They are inherently unstable and can release at any time.

Snowpack Summary

20-40 cm of new snow has been accumulating incrementally over recent days. Depending on the time of day, moist snow or a crust can be found on solar aspects and below 1700 m. Isolated, soft wind slabs can be found in lee features of wind exposed alpine terrain. The snowpack is otherwise well settled and strong.

Terrain and Travel

  • Be alert to conditions that change with elevation.
  • Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
  • Small avalanches can have serious consequences in extreme terrain. Carefully evaluate your line for wind slab hazard before you commit to it.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Wind Slabs

An icon showing Wind Slabs

Watch for wind loaded pockets in lee terrain features such as beneath ridge crests and roll-overs.

Cornices are large, looming and need to be given their space from above and below.

Aspects: North, North East, East, South East, South.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Mar 25th, 2021 4:00PM