Avalanche Forecast

Issued: Apr 29th, 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.

JH, Avalanche Canada

Glacier.

If the terrible travel conditions don't deter you, hopefully the elevated avalanche hazard will.

It's a good time to go biking, or sport climbing, or maybe just lounge in the sun.

Summary

Confidence

High

Avalanche Summary

Numerous loose snow and slab avalanches were observed on Friday and Saturday. Avalanches were up to size 3 and are starting to gouge further into the snowpack. Several deeper slab avalanches are suspected to have failed on the Mar. 31st crust.

Avalanches may to continue to increase in size as the snowpack warms.

Snowpack Summary

At upper elevations, warm temperatures and minimal overnight refreeze is weakening a moist upper snowpack. Several crusts buried in the top 50cm of the snowpack are beginning to break down as the snow warms. 20-40cm above the ground, the Nov 17 basal weakness can still be found in many areas.

Below treeline, the entire snowpack has become isothermal, and is losing strength as the day warms.

Weather Summary

Warm, sunny weather through the weekend, with above seasonal temps and high freezing levels (FZL).

Tonight: Mostly clear, Alpine Low 9Â°C, FZL 3300m, Light SW ridgetop wind.

Sun: Mixed sun/cloud, High 14Â°C, FZL 3500m, Light SE wind.

Mon: Showers (10mm), Low 7Â°C, High 13Â°C, FZL 3700m.

Tues: Showers (9mm), Low 7Â°C, High 11Â°C, FZL 3600m.

Terrain and Travel Advice

The more the snow feels like a slurpy, the more likely loose wet avalanches will become.
If triggered loose wet avalanches may step down to deeper layers resulting in larger avalanches.
Avoid exposure to overhead avalanche terrain as temperatures increase.

Problems

Loose Wet

With intense solar heating and very little overnight refreeze the surface snow is moist and weak. Loose wet avalanches are easily triggered in steep terrain and can gain surprising mass.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

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 - Very Likely

Expected Size

2 - 3

Deep Persistent Slabs

The increasing warmth is penetrating deep into the snowpack. The potential for this early season basal weakness to wake up and produce very destructive avalanches increases with each day of warming.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 4.5

Valid until: Apr 30th, 2023 8:00PM