Avalanche Forecast

Issued: Mar 9th, 2023 4:00PM

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

Avalanche Canada trettie, Avalanche Canada

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Keep an eye out for blowing snow. New thin wind slabs could form throughout the day near ridge crests.

Summary

Confidence

Moderate

Avalanche Summary

No significant avalanches were reported on Wednesday.

On Saturday, explosive avalanche control work resulted in numerous very large(size 3-4) persistent slab avalanches. They occurred on a variety of aspects below steep, wind loaded treeline ridgetops and large alpine features.

Snowpack Summary

 

A new sun crust exists on solar aspects. Recent southeasterly winds have formed wind slabs near ridge crests at higher elevations. These slabs are sitting on either hard surfaces or small facets. The above mentioned winds have formed large cornices.

There are several crusts in the mid/lower snowpack. Their depth ranges from 150-200 + cm.

A large trigger, such as a cornice fall or smaller avalanche in motion, could trigger a very large avalanche on one of these deeply buried weak layers. A single rider is unlikely to trigger this layer unless they are in a steep, rocky, and shallow snowpack area.

Weather Summary

Thursday Night

Mostly cloudy with the possibility of light flurries bringing trace amounts of new snow. Light to moderate southeast winds and a low of -8°C at 1800 m.

Friday

Cloudy with around 5 cm of new snow. Light easterly winds shifting to light southwest winds in the afternoon. High of -4°C at 1800 m with freezing levels rising to 1200 m.

Saturday

Mostly cloudy with flurries bringing a few centimeters of new snow. Light to moderate southerly winds and a high of -5°C at 1800 m.

Sunday

A mix of sun and cloud with no new snow expected. Moderate southerly winds and freezing levels rising to 1500 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
  • Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.
  • Minimize your exposure time below cornices.

Problems

Wind Slabs

An icon showing Wind Slabs

New thin wind slabs could form near ridge crests throughout the day. These new slabs will form over old wind slabs formed a couple days prior.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

There are several crusts in the mid/lower snowpack. Their depth ranges from 150-200 + cm.

A large trigger, such as a cornice fall or smaller avalanche in motion, could trigger a very large avalanche on one of these deeply buried weak layers. A single rider is unlikely to trigger this layer unless they are in a steep, rocky, and shallow snowpack area.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1.5 - 3

Valid until: Mar 10th, 2023 4:00PM