Avalanche Forecast

Issued: Mar 21st, 2023 4:00PM

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

Avalanche Canada jsmith, Avalanche Canada

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Lingering wind slabs may remain reactive to human triggers on northerly aspects in the alpine.

Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.

Summary

Confidence

High

Avalanche Summary

A naturally triggered size 1.5 wind slab avalanche was reported on a west aspect at treeline on Monday.

Several naturally triggered size 1-1.5 wet loose avalanches were reported on sunny aspects at upper elevations.

A large (size 2.5) rider triggered wind slab was reported on a north aspect in the alpine on Friday. The avalanche was triggered from the ridge top and the reported weak layer was surface hoar. See MIN.

Snowpack Summary

Expect to find a melt-freeze crust on the surface of all aspects at treeline and below and on sunny aspects in the alpine. Solar radiation will break down the crust on sunny slopes throughout the day.

Lingering wind slabs may remain reactive to human triggers on northerly aspects in the alpine.

30-50 cm down there is a sun crust on sunny aspects and surface hoar (3-5 mm) on isolated shady and sheltered slopes.

Another layer of surface hoar or sun crust, aspect dependent, that was formed in mid-February can be found down 80 to 110 cm.

The lower snowpack includes a layer of weak sugary facets near the ground. These facets are slowly gaining strength and no recent avalanches have been reported on this layer. However, we continue to track the layer and watch for any signs of it becoming active.

Weather Summary

Tuesday Night

Clear skies / 10 km/h northeast ridgetop wind / Temperature at treeline around -6 C / Freezing level valley bottom

Wednesday

Sunny / 10 km/h northeast ridgetop wind / Temperature at treeline around 1 C / Freezing level 2100 m

Thursday

Mostly sunny / 20 km/h southwest ridgetop wind / Temperature at treeline around -3 C / Freezing level 1600 m

Friday

Cloudy with isolated flurries; 0-3 cm / 20 km/h southwest ridgetop wind / Temperature at treeline around -7 C / Freezing level 1300 m

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Cornice failure may trigger large avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Lingering wind slabs may remain reactive to human triggers on northerly aspects in the alpine.

Aspects: North, North East, North West.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet

Strong solar radiation will increase the likelihood of wet loose avalanches on sunny aspects in the alpine.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 22nd, 2023 4:00PM