Avalanche Forecast

Issued: Jan 8th, 2019 4:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Deep Persistent Slabs.

ian jackson, Parks Canada

Banff Yoho Kootenay.

Touchy conditions persist. Give those deep layers some time to adjust to the new load.

Summary

Weather Forecast

Warmer temperatures and some light precipitation are coming Wednesday and into Thursday. Only 5- 15 cm is expected by end of day Thursday. Winds will be moderate to strong SW on Wednesday night/ Thursday. Friday should see a clearing and cooling trend with the winds dyeing down.

Snowpack Summary

Up to 70 cm of snow of recent snow with variable wind effect has put a dense load over the persistent weak layers. In thicker snow pack areas, the Dec. 10th weak layer of facets is now down 100-150cm with a stronger snowpack below. In thin snowpack areas, the Dec.10th layer is mixed in with the basal facets and October crust.

Avalanche Summary

The natural avalanche cycle has tapered off, but conditions are still primed for human triggering. A localized natural cycle in the Sunshine area was likely triggered by winds, showing how touchy it still is in many areas. In the Lake Louise area, a small but deep slab was triggered just outside of the ski hill boundary in a small treeline opening

Confidence

Due to the number and quality of field observations

Problems

Deep Persistent Slabs

Avalanche control work on Monday proved that this layer is still touchy. Most avalanches scrubbed down to the October 26th facet crust or the ground. This layer needs time to adjust to the load and this problem will be around for some time.

Be aware of the potential for wide propagations which could result in large avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 3.5

Valid until: Jan 9th, 2019 4:00PM