Avalanche Forecast

Issued: Mar 29th, 2023 4:00PM

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

Avalanche Canada ahanna, Avalanche Canada

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Increasing cloud, cooler temperatures and wind are expected to keep the snow surface cooler on Thursday than previous days. Still carefully consider your exposure if you find the snow surface to be moist or wet.

Summary

Confidence

Moderate

Avalanche Summary

Most avalanche activity this week has been limited to small (size 1) wet loose.

However, a few outliers - large slab avalanches - have been reported throughout the region. Although we don't think we have a widespread problem at this point, it's something to keep in mind as the spring warms up. On Monday south of Terrace, a size 2.5 wet slab was reported out of a steep, rocky start zone on a northwest aspect around treeline. On Tuesday, a couple of large avalanches (size 2.5-3) with deep crowns were observed in the alpine north of Stewart. These are suspected to have been cornice-triggered and to have run on a weak layer buried in January that hasn't otherwise shown reactivity for several weeks.

Other natural cornice failures have been observed, not triggering slabs on slopes below.

Snowpack Summary

Moist snow or a crust exists on the surface on all aspects below treeline and on steep south facing slopes treeline and above. Dry snow can be found on shady aspects at upper elevations, wind-affected and well-settled.

The lower snowpack is well consolidated and strong.

Weather Summary

Wednesday night

Clear. Light variable wind. Alpine low -4 °C. Freezing level 1500 m dropping to valley bottom.

Thursday

Increasing cloud. Wind increasing to moderate southwest. Alpine high -2 °C. Freezing level 1000 m.

Friday

8-15 cm of new snow. Strong southwest wind. Alpine high -4 °C. Freezing level 900 m.

Saturday

Around 5 cm overnight then clearing to a mix of sun and cloud. Light southwest wind. Alpine high -5 °C. Freezing level 800 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
  • Watch for unstable snow on specific terrain features, especially when the snow is moist or wet.
  • A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
  • Avoid exposure to slopes that have cornices overhead.

Problems

Loose Wet

An icon showing Loose Wet

Potential for loose wet avalanches may remain in areas that have poor overnight refreeze.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

1 - 1.5

Cornices

An icon showing Cornices

Cornices become weak with daytime heating or solar exposure. Avoid overhead exposure to cornices and give them a wide berth when travelling on ridges.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Mar 30th, 2023 4:00PM