Archived

Avalanche Forecast

Apr 9th, 2022–Apr 10th, 2022

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

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

Alpine

1: Low

The avalanche danger rating in the alpine will be low

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: Glacier.

Conditions at lower elevations will be firm as a result of the cooling temps, but winter snow can still be found on high north aspects.

Enter your line cautiously, there is a fresh windslab problem to manage.

Weather Forecast

Cooling temps and convective flurries are the current pattern.

Tonight: Clear periods, Alpine low -12*C, Light NW ridgetop wind

Sunday: Sun to start, convective flurries in the PM, High -8*C, Freezing level (FZL) 1100m, Light NE wind

Mon: Mainly sunny, Low -14*C, High -9*C, FZL 900m, Light E wind

Tue: Sunny periods, Low -17*C, High -11*C, Light E wind

Snowpack Summary

Below treeline the spring snowpack has undergone several melt-freeze cycles.

Up high, mod-strong SW wind is redistributing up to 15cm of new snow, which overlies a crust on all but N'rly alpine slopes where it's on settled dry snow.

Persistent crust layers from late March, and the deeply buried Dec 1st crust, may awaken with large triggers/cornices.

Avalanche Summary

Neighboring operations have seen sporadic very large avalanches failing on persistent/deep persistent crust layers recently.

Glide cracks have been on the move lately, with a size 2 glide slab avalanche from the S aspect of Mt. Tupper early on Saturday, a size 3 from S Mt. Tupper on Friday, and another size 3 from the S side of Cheops on Wednesday.

Confidence

Due to the number of field observations

Avalanche Problems

Wind Slabs

New snow and moderate winds have built fresh windslabs in lees. These may sit over a crust on slopes with sun exposure.

Watch for shooting cracks or stiffer feeling snow. Avoid areas that appear wind loaded.
Use caution above cliffs and terrain traps where small avalanches may have severe consequences.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2.5

Persistent Slabs

The March 31 crust is down 30-70 cm, and was reactive to skier triggering locally early in the week.

The March 31st and Dec 1st crust (near the base of the snowpack) have been producing sporadic large to very large natural avalanches nearby recently.

Pay attention to overhead hazards like cornices which could trigger the persistent slab.
If triggered small avalanches may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely

Expected Size: 1.5 - 3.5