Avalanche Forecast

Issued: Jan 14th, 2019 3:00PM

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

michael.olsthoorn, Alberta Parks

Kananaskis.

The basal facet problem has been the sliding layer for the last two natural avalanches. This problem will be with us for a long time. Stay disciplined.

Summary

Confidence

High -

Weather Forecast

Tuesday and Wednesday are forecast to bring a mix of sun and cloud along with light SW winds and alpine temps around -7c.We have had a temperature inversion(cold in the valley bottom and warm up high) for the last couple of days and we might see this again for Tuesday. Light flurries are expected for Thursday.

Avalanche Summary

One natural size 2 slab avalanche occurred sometime during Sunday night in a west facing gully off of Mt. Buller. The failure plane was mostly on the basal facets and scrubbed to ground.

Snowpack Summary

Wind slabs are pretty much everywhere in the alpine and open areas at tree line. The upper half of the snowpack is well settled and comprised of two hard layers, each around 35cm thick. The upper hard layer is still producing moderate test results on what appears to be the December 30 facets. The lower hard layer is resting on the Dec 10 facets(start of the basal facets) which is approximately 70cm down. The basal facets make up the bottom 50-60cm of the snow pack. We had several repeatable compression tests(sudden planar) in the moderate to hard range that occurred on the basal facets.Have a look on our Facebook page for our latest video showing the compression test on the basal facets: https://www.facebook.com/KCPublicSafety/

Problems

Wind Slabs

Wind slabs are widespread in the alpine and in open areas at tree line. Steeper alpine features and thin spots are places to avoid.

Avoid convexities or areas with a thin or variable snowpack.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Deep Persistent Slabs

Any avalanche has the potential to trigger the basal facets, resulting in large avalanches.

Carefully evaluate and use caution around thin snowpack areas.Remote triggering is a concern, watch out for adjacent slopes.Be aware of the potential for full depth avalanches due to weak layers at the base of the snowpack.

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

Elevations: All elevations.

Likelihood

Likely

Expected Size

1.5 - 3

Valid until: Jan 15th, 2019 2:00PM