Avalanche Forecast

Issued: Apr 4th, 2021 4:00PM

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

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Watch for cornices and wind slabs near ridgetops.

Summary

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

SUNDAY NIGHT: Cloudy, 40 km/h west wind, treeline temperatures drop to -7 C.

MONDAY: Cloudy with light flurries in the afternoon with trace accumulations, 40 km/h west wind, treeline temperatures around -4 C.

TUESDAY: Scattered flurries with up to 5 cm of new snow, 20 km/h southwest wind, treeline temperatures around -4 C.

WEDNESDAY: Mix of sun and cloud with some light flurries, 20 km/h west wind, treeline temperatures around -4 C.

Avalanche Summary

Reports from Saturday included a few isolated avalanches with some size 1-2 cornice failures, one size 2 wind slab on a southeast aspect, and one size 2 wet loose avalanches on a south-facing slope.

Snowpack Summary

Small wind slabs formed by light amounts of recent snow and southwesterly winds may linger below alpine ridgetops. A firm crust exists at lower elevations. Cornices are large and looming at this time of year.

Buried 70-120 cm. deep, a spotty layer of surface hoar may exist on sheltered north aspects, but no recent avalanches have been reported on this layer. 

The 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

  • Carefully evaluate steep lines for wind slabs.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Avoid exposure to slopes that have cornices overhead.

Problems

Cornices

An icon showing Cornices

Cornices are large and looming along many ridgelines, and have likely grown with the recent wind.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1.5 - 2.5

Wind Slabs

An icon showing Wind Slabs

Lingering wind slabs may remain reactive to human triggers. Use caution when transitioning into wind affected terrain.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 1.5

Valid until: Apr 5th, 2021 4:00PM