Archived

Avalanche Forecast

Apr 18th, 2017–Apr 19th, 2017

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Banff Yoho Kootenay.

Conditions are highly variable right now, and the danger ratings represent the highest danger rating for the day. Avalanche danger is lower in the morning when the snow surface is frozen, and before the air temperatures warm up. Start early.

Weather Forecast

Clearing through the day on Wednesday, with sun patches appearing in the afternoon. Expect a high of 0 degrees at treeline, and lows of -10 early in the morning. Trace amounts of snow expected overnight for Wednesday.

Snowpack Summary

The snowpack is a real mixed bag right now: totally dependent on aspect and elevation. At treeline and above, 5-10 cm of new snow overlies a strong melt-freeze crusts to ridge top on solar aspects, and 2000m on north aspects. Below treeline the snowpack becomes wet through the day. The snowpack has not converted to spring conditions yet.

Avalanche Summary

No new avalanches reported or observed today.

Confidence

Avalanche Problems

Loose Wet

Afternoon warming will create loose wet problems at low elevations and on S and W facing terrain at higher elevations.

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2

Cornices

Cornices continue to fail. Minimize your time underneath these and remember that a cornice failure could also trigger the deep persistent slab on the basal facets.

Aspects: North, North East, East, South East, South.

Elevations: Alpine.

Likelihood: Possible - Likely

Expected Size: 1 - 3

Deep Persistent Slabs

The snowpack is gaining strength, but the weak basal facets continue to produce sudden collapse results and can produce large avalanches with large triggers. Stick to planar, supported slopes with a deeper snowpack if entering steep terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 2 - 4