Avalanche Forecast

Issued: Apr 4th, 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 isnowsell, Avalanche Canada

Email

Unsettled, spring weather can deliver localized periods of intense sun or heavy snowfall, which can temporarily increase the avalanche hazard.

Summary

Confidence

Moderate

Avalanche Summary

On Sunday a size 3 naturally triggered, deep persistent slab avalanche was reported in the western Purcells (southwest of Panorama). It occurred in large alpine terrain, west facing at 2800 m.

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

Variable amounts of recent snow overlay various old surfaces, including a hard crust on solar aspects and spotty surface hoar on sheltered, northerly terrain. Wind slabs may persist in steep, exposed lee 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 continues to be responsible for several very large and destructive avalanches throughout the season.

Weather Summary

Tuesday night

Mostly clear, with periods of cloud and scattered flurries. Light west ridgetop wind. Alpine temperatures -5 to -10 C. Freezing level at valley bottom.

Wednesday

Mix of sun and cloud. Light southwest ridgetop wind. Alpine temperatures -5 to -10 C. Freezing level 1600 m.

Thursday

Mix of sun and cloud. Light southwest ridgetop wind. Alpine temperatures 0 to -5 C. Freezing level 1900 m.

Friday

Mostly cloudy. Moderate south ridgetop wind. Alpine temperatures 0 to -5 C. Freezing level 1900 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.

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

Wind and storm slabs may persist in alpine areas that have received more recent snow and/or wind.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Apr 5th, 2023 4:00PM