Archived

Avalanche Forecast

Apr 23rd, 2018–Apr 24th, 2018

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

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

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

Regions: Glacier.

Rising freezing levels and strong solar input will bring increasing avalanche danger over the day.

Weather Forecast

A prolonged high pressure period begins today. Freezing levels should rise to 2100m with light ridge winds today. Tuesday freezing levels rise to 3100m with an alpine high of +4C. Freezing levels continue to rise later in the week with little or no overnight recovery.

Snowpack Summary

30cm storm snow over the weekend and moderate S through SW winds have formed wind slab on alpine lee slopes. At lower elevations storm snow insulates the old moist snow surface. Dry snow still exists on N'ly aspects at high elevations. Cornices and wind loading lurk above treeline. The April 7 crust is now down 60cm and still a concern.

Avalanche Summary

On the flanks of Mt Tupper the glide crack in Mounds slide path released naturally sometime overnight and ran size 3.5. Yesterday afternoon Cheops North 1 ran size 2.5. It is possible that this slide was human triggered as skiers were in the area. Yesterday our field team was able to push moist surface sluffs to size 0.5 below 1700m on a W aspect.

Confidence

The weather pattern is stable

Avalanche Problems

Loose Wet

Loose wet surface slides can be expected off of solar aspects as daytime warming and direct sunshine destabilize surface layers. These slides may dig deeper as underlying snow is moist.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.Plan to finish your tour early.

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

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 2.5

Cornices

Cornices are large and ripe. They will become more prone to failure with daytime warming and solar input.

Avoid steep slopes below cornices.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 2.5

Wind Slabs

Thin surface windslab can be expected on northerly aspects in the alpine.

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

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 2.5