Archived

Avalanche Forecast

Mar 11th, 2016–Mar 12th, 2016

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

1: Low

The avalanche danger rating below treeline will be low

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

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

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Banff Yoho Kootenay.

Watch for sudden intense solar heating. Also, the windslabs will continue to build and are likely to remain touchy to human triggering for a while. Avoid large open avalanche slopes and thin or unsupported slopes until the snowpack settles.

Weather Forecast

Warmer temps on Saturday with a little sun and snow. Then cooler again with ongoing snow, wind and sun.

Snowpack Summary

Two smaller, recent storms have left 20-50 cm of snow poorly bonded to the old crusts below. Recent moderate S-SW winds with strong gusts have formed slabs in lee areas. A firm upper snow pack sits over a weak mid-pack of facets & depth hoar. In thin snowpack areas tests results are typically collapses near the ground.

Avalanche Summary

Numerous avalanches to size 2.5 occurred Thursday morning after the passing of the storm. Most appeared to be windslabs in lee or cross-loaded areas.

Confidence

Timing or intensity of solar radiation is uncertain

Avalanche Problems

Deep Persistent Slabs

The mid-pack facets remain weak, especially in thin or rocky areas. Avoid steep or unsupported terrain, and watch for signs of instability such as whumphing and cracking.

Be aware of thin areas that may propogate to deeper instabilites.Caution around convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 3

Wind Slabs

Recent W winds and new snow have created soft slabs in lee areas and cross-loaded features.

If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2