Avalanche Forecast

Issued: Apr 26th, 2023 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is below threshold. Known problems include Deep Persistent Slabs, Loose Wet and Storm Slabs.

Avalanche Canada SH, Avalanche Canada

Email

We expect rising hazard throughout the day Thursday due to solar input. The deep persistent layer is still a major concern and should become more active in the coming days. Starting Friday, we will see 3000-3500m freezing levels and likely a large avalanche cycle.

Summary

Confidence

Moderate

Avalanche Summary

A couple of loose wet avalanches in very steep, East facing terrain today in the Sunshine Village backcountry, but no other avalanches were observed or reported Wednesday.

Snowpack Summary

Thick crusts on all aspects werent breaking down today over 2000m. In general, solar aspects are getting moist in the afternoon, creating new crusts daily, and multiple buried crusts are present. On northerly aspects, temperature crusts are present up to 2200m (maybe higher), with 10-20 cm of preserved surface snow above this elevation. The base of the snowpack remains weak due to the presence of facets and depth hoar.

Weather Summary

Around 5cm of snow Wednesday night with freezing levels near valley bottom.

Thursday: Clearing skies and 2500m freezing levels, NW winds 40km. Overnight Thursday freezing levels to valley bottom, but temperatures will be inverted at 2000m with warmer air above.

Friday: NW winds, mainly clear skies. Freezing levels will spike to 3000-3500m.

Terrain and Travel Advice

  • A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The weak basal facets and mid-pack facets/crusts will remain a concern for the foreseeable future. Daytime heating may also increase the likelihood of triggering this weakness. Stick to well supported lower angle terrain to avoid this problem.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 3.5

Loose Wet

An icon showing Loose Wet

With rising daytime freezing levels, expect moist snow at lower elevations with the potential for wet loose avalanches to occur. Any sunny breaks will also contribute to this problem on steep solar aspects up into the alpine.

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

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Storm Slabs

An icon showing Storm Slabs

Watch for new snow instabilites especially in places where convective weather cells have deposited more snow. Areas with new snow over a crust, recently wind loaded slopes, or places where the surface snow is becoming moist are the main concerns.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 27th, 2023 4:00PM