Avalanche Forecast

Issued: Apr 1st, 2021 4:00PM

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

Avalanche Canada JSmith, Avalanche Canada

Email

Moderate to strong winds from shifting directions are forming fresh wind slabs on lee features at treeline and above on a variety of aspects. Stay alert to changing conditions with elevation and aspect to avoid wind loaded slopes.

Summary

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

  

THURSDAY NIGHT: Cloudy with flurries; 3-5 cm. / Strong, southwest ridgetop wind / alpine low temperature -11 / Freezing level valley bottom.

FRIDAY: Snow/rain; 3-10 mm, and another 5-10 cm. overnight / Strong, southwest ridgetop wind / alpine high temperature -2 / Freezing level 800 m.

SATURDAY: Cloudy with isolated flurries; 0-3 mm. / Light, south ridgetop wind / alpine high temperature -1 / Freezing level 900 m.

SUNDAY: Mix of sun and cloud / Strong, northwest ridgetop wind / alpine high temperature -1 / Freezing level 900 m.

Avalanche Summary

On Wednesday, naturally triggered wet loose avalanches up to size 1.5 were reported on steep solar aspects.

Snowpack Summary

Moderate to strong winds from shifting directions are forming fresh wind slabs on lee features at treeline and above on a variety of aspects. A firm crust exists at lower elevations.

Buried 70-120 cm. deep, a spotty layer of surface hoar may exist on sheltered north aspects, as well as a crust on south aspects and below 1500 m. Recent observations suggest that this interface is bonding.

The mid and lower snowpack is reported as well settled and strong in most areas. However, weak facets exist at the base of the snowpack in the more shallow snowpack zones within much of the region and have the potential to be triggered on steep, rocky slopes with a shallow or thin to thick snowpack; especially with large loads such as a cornice fall.

Terrain and Travel

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Avoid freshly wind loaded terrain features.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
  • Caution around slopes that are exposed to cornices overhead.

Problems

Wind Slabs

An icon showing Wind Slabs

Moderate to strong winds from shifting directions are forming fresh wind slabs on lee features at treeline and above on a variety of aspects.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Cornices

An icon showing Cornices

Cornices are large and looming along many ridgelines, and have likely grown with the recent snow and wind. They require a large berth from above and below.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Apr 2nd, 2021 4:00PM

Login