Avalanche Forecast

Issued: Dec 26th, 2018 4:20PM

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

brian webster, Parks Canada

Banff Yoho Kootenay.

The snowpack is slowly starting to stabilize however forecasters confidence is low. Remember that human triggered avalanches are still possible with a Moderate danger rating. It is still a good idea to avoid bigger features and convex terrain.

Summary

Weather Forecast

Thursday will bring a mix of sun and cloud with day time highs (at treeline) of -5 to -8. Winds forecasted to be light and there is no snow in the forecast through Friday. More snow and stronger winds are expected on Saturday.

Snowpack Summary

In deeper snowpack areas there is 60-80 cm of settled snow over top of the Dec10 surface hoar/facet layer. Shears on this layer are generally producing hard but sudden planar results. In shallow areas the main concern is the weak basal facets which continue to produce whumphing and easy test results. Extra caution is warranted in shallow areas.

Avalanche Summary

One fresh natural avalanche observed on Observation Pk. Ski hills reported no new natural activity and only minimal results with explosives.

Confidence

Problems

Deep Persistent Slabs

This problem dominates the central and eastern part of the forecast region and will continue to do so for some time. Natural activity on this layer has decreased but human triggered avalanches on this layer are still possible.

Be wary of large slopes that did not previously avalanche.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1.5 - 3

Persistent Slabs

This problem is the Dec 10 surface hoar/facet layer which is down 40-80 cm along the Divide. Although this layer is stabilizing, there is still uncertainty with this interface. Evaluate this layer carefully prior to committing to bigger slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Dec 27th, 2018 4:00PM