Archived

Avalanche Forecast

Jan 15th, 2018–Jan 16th, 2018

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Little Yoho.

Likelihood of triggering the Dec 15th layer at treeline is higher in Little Yoho. Make conservative terrain choices and avoid open uniform slopes at treeline.

Weather Forecast

The temperature inversion will continue until Tuesday morning. Expect alpine temperatures to remain near 0 degrees. A cooling trend is expected thereafter. Cloud cover and the start of light precip will begin late on Tuesday. Accumulations of up to 10cm are expected by the end of Thursday. Wind will pick up to moderate from the SW throughout Tues.

Snowpack Summary

Continued warm alpine temperatures and clear skies moistening the upper snowpack on steep S-W aspects. 30-50cm over the Dec.15 persistent weak layer of facets and surface hoar. This Dec 15th layer is reactive to skiers at treeline and above and producing easy to moderate snowpack test results. Below this is a heavily faceted snowpack.

Avalanche Summary

Avalanche control produced results up to size 2.5 today on Hwy 93S and the Sunshine Road. The larger avalanches were produced on uniform terrain features at treeline where the Dec 15th surface hoar was present. No reports today from Little Yoho, but concern remains.

Confidence

Avalanche Problems

Wind Slabs

Wind slabs are present in the alpine and near ridge crests at treeline in isolated areas. Watch for the changing feel of the snow under your feet and be wary of areas with denser surface snow over weaker snow.

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Use caution in lee areas. Recent wind loading has created wind slabs.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 2

Persistent Slabs

This layer is a concern mainly at treeline. Easy test results and reports of significant whumps and cracks show the potential for this to be a dangerous problem. Exercise a high degree of caution on uniform open features at treeline.

Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.Choose conservative lines and watch for clues of instability.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3