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 Loose Wet and Storm Slabs.

Avalanche Canada SH, Avalanche Canada

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We expect rising hazard throughout the day Thursday due to solar input. Start and end early before this occurs. Starting Friday, we will see 3000-3500m freezing levels and likely a large avalanche cycle.

Summary

Confidence

Moderate

Avalanche Summary

No new avalanches were observed or reported in Little Yoho Wednesday.

Snowpack Summary

Thick crusts on all aspects weren't breaking down Wednesday 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 2200 m, with 10-20 cm of preserved surface snow above this elevation. There are basal facets in some thin locations but they have been mainly dormant.

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.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Problems

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