Archived

Avalanche Forecast

Apr 7th, 2022–Apr 8th, 2022

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

3: Considerable

The avalanche danger rating below treeline will be considerable

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Banff Yoho Kootenay.

Likely a poor freeze Friday AM, and it is hard to estimate the danger ratings for these conditions. Watch locally for how much freeze occurs and for wind slabs in the alpine. Cooler temperatures are coming next week which should improve conditions.

Weather Forecast

There will likely be a poor freeze overnight into Friday with a slight temperature inversion. Alpine winds will increase into the strong range, weakening over the course of the day. Timing us uncertain, but snow will begin as the passage of a cold front moves in mid-day. So far 5-15cm is expected. Cooler temperatures arrive Friday night onward.

Snowpack Summary

15-20 cm of soft, dry snow sits on a firm crust on N aspects down to at least 2000m. On solar aspects a series of crusts exist in the snowpack at all elevations, starting to break down on Thursday with warming. Windslabs exist in immediate leeward areas of ridges, and are still capable of being triggered.

Avalanche Summary

FIeld trip near Sunshine Village on Wednesday observed a size 1.5 windslab/cornice on a SE aspect and a fresh cornice failure on the N side. Some other reports from Lake Louise backcountry and below the Bow Hut in last 24 hours of wind slabs being triggered up to size 1.5 in the alpine.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Friday

Avalanche Problems

Wind Slabs

Windslabs exist near ridge crests, and will likely stay sensitive with warm temperatures and incoming snow. Pay close attention near ridges and entrances to ski lines.

Use caution in lee areas. Recent loading has created reactive slabs.

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

Elevations: Alpine.

Likelihood: Possible - Likely

Expected Size: 1 - 2

Loose Wet

There is uncertainty about how the snowpack will react to a poor freeze. Backcountry users will have to monitor this locally on their trip.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2

Cornices

Cornices may become more sensitive to triggering or falling off while the temperatures stay warm over the next 24 hours. This is a big consideration if the trip you are considering has overhead exposure to them.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 3