Avalanche Forecast

Issued: May 1st, 2023 4:00PM

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

CG, Avalanche Canada

Glacier.

Any avalanche start zone that still holds snow should be avoided. Wet, loose "slurpee" slop is the best way to describe the snowpack at the moment. With continued hot temps to mtn-top, stay away from all avalanche terrain!

Summary

Confidence

High

Avalanche Summary

Avalanche control from Sunday produced excellent results, with wet/loose avalanches gathering up the winter snowpack and bulldozing it down to the valley bottom. Many slidepaths failed down to ground once the avalanches reached Treeline elevations and lower.

Any start zone that still holds snow right now should be avoided!

Snowpack Summary

Warm temps and no overnight refreeze have produced a weak, moist upper snowpack at all elevations. Several crusts are buried 30-50cm but are breaking down as the snow warms up.

Below Treeline the snowpack is wet and weak, 20-40cm above the ground the Nov 17 basal weakness can still be found in many areas.

Weather Summary

Warm weather continues with above seasonal temps, high freezing levels (FZL), and no overnight freeze in the Alpine.

Tonight: Mostly clear, Alpine Low 10°C, FZL 3700m, Light E ridgetop wind

Tues: Mix of sun/cloud, Alpine High 14°C, FZL 3800m, light E winds

Wed: sun/cloud/isolated showers, Alpine high 14°C, FZL 3700m, light S winds

Terrain and Travel Advice

The more the snowpack warms-up and weakens, the more conservative you`ll want to be with your terrain selection.
As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.
The likelihood of deep persistent slab avalanches will increase with each day of warm weather.
Minimize overhead exposure; avalanches triggered by warming or cornice fall may be large and destructive.

Problems

Loose Wet

With intense solar heating and no overnight refreeze, the surface snow is moist and weak. Loose, wet avalanches are easily triggered in steep terrain and reliably gain enough mass to step down to the basal weakness at Treeline elevations and lower.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 4

Wet Slabs

Several buried crusts exist in the upper snowpack, the deepest of which is the Mar 31 layer. As the upper snowpack loses strength and cohesion during this intense warm up these crusts may provide a failure plane for the wet snow.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 3

Deep Persistent Slabs

The increasing warmth is penetrating deep into the snowpack. This early season basal weakness has woken up below 2000m and is producing very destructive avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 4

Valid until: May 2nd, 2023 4:00PM