Avalanche Forecast

Issued: Apr 2nd, 2023 4:00PM

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

Avalanche Canada mbender, Avalanche Canada

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An unstable weather pattern will bring clouds, sun and flurries over the next couple of days. Sporadic flurries and wind will continue to promote wind slab formation at upper elevations.

Summary

Confidence

Moderate

Avalanche Summary

On Friday a size 3 naturally triggered avalanche was reported in the Dogtooth Range. While the failure plane is unknown the report mentions impressive propagation.

Snowpack Summary

New snow and wind have formed wind slabs at upper elevations. Surface hoar may exist below the recent snow, in wind sheltered and shaded terrain.

The mid snowpack may still contain a few persistent weak layers of surface hoar in sheltered treeline terrain. No recent avalanche activity has occurred on these layers suggesting the layers have gained strength.

The lower snowpack includes a widespread layer of large, weak facets and or depth hoar crystals. This weak layer was responsible for a number of very large and destructive avalanches through the season and right up to last week during a warm sunny period. This will continue to be a concern for the rest of the season.

Weather Summary

Sunday Night

Mostly cloudy with scattered flurries, accumulation 1-4cm. Light southwest wind. Alpine high of -7 °C. Freezing level at valley bottom.

Monday

Mostly cloudy with sunny breaks and scattered flurries, accumulation 1-5cm. Light northeast wind. Alpine high of -6 °C. Freezing level 1500 m.

Tuesday

Mostly cloudy with sunny breaks and scattered flurries, accumulation 1-5cm. Light east wind. Alpine high of -5 °C. Freezing level 1500 m.

Wednesday

Mix of sun and cloud. Light southwest wind. Alpine high of -3 °C. Freezing level 1700 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The base of the snowpack remains very weak. Avoid thin, rocky start zones and shallow areas with variable snowpack depths.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2.5 - 4

Wind Slabs

An icon showing Wind Slabs

Recent new snow and wind have likely promoted wind slab development in exposed lee terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 3rd, 2023 4:00PM