Archived

Avalanche Forecast

Apr 26th, 2023–Apr 27th, 2023

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

Below Threshold

The avalanche danger rating below treeline will be below threshold

Alpine

4: High

The avalanche danger rating in the alpine will be high

Treeline

4: High

The avalanche danger rating at treeline will be high

Below Treeline

Below Threshold

The avalanche danger rating below treeline will be below threshold

Alpine

4: High

The avalanche danger rating in the alpine will be high

Treeline

4: High

The avalanche danger rating at treeline will be high

Below Treeline

4: High

The avalanche danger rating below treeline will be high

Regions: Little Yoho.

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.

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.

Avalanche Problems

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

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