Avalanche Forecast

Issued: Dec 30th, 2016 3:00PM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is low. Known problems include Wind Slabs, Persistent Slabs and Loose Dry.

matt.mueller, Alberta Parks

Kananaskis.

Some new snow has helped perk up the ski quality and valley bottom travel. Sheltered areas will be the place to be for the next while.

Summary

Confidence

High -

Weather Forecast

Mostly clear overnight with winds increasing at ridgeline. Tomorrow will see isolated flurries develop, but little accumulation. The alpine high will be -15. Winds will continue to increase, settling at 40-50km/hr from the west.

Avalanche Summary

-Numerous loose dry avalanches noted today on all alpine aspects. -Explosive control (Mt Rundle) produced a few sz 2's. Most of the avalanche volume came from entrainment of loose snow within the path.-A few slab avalanches noted at the base of cliffs in alpine terrain. Up to sz 2 and on east aspects.

Snowpack Summary

10-20 cm's of new snow fell last night. At treeline, the windslabs are now buried and somewhat disguised under the unsettled, new snow. Little wind today has done almost nothing for fresh storm slab development. The Dec 18 facet layer is now down 50cm on average. In the alpine, similar conditions exist due to the lack of significant wind. The only exception is in windward areas (westerly aspects) that saw intense wind scouring earlier in the week. Expect isolated(immediate lee) storm slabs and extensive windslabs on N to S aspects. The new snow is still low density with little cohesion.

Problems

Wind Slabs

These slabs are buried and may be difficult to find until you are standing on them. Start to look for them as you approach open terrain at treeline and alpine elevations. A lack of natural activity suggests that these are prime for human triggering.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Persistent Slabs

This layer will be further stressed by the new load and potential for new wind loading. Like the windslabs, these are also primed and ready to avalanche. Avoid large terrain while this layer adjusts to the new load.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.Be aware of the potential for wide propagations.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Very Likely

Expected Size

2 - 3

Loose Dry

Steep terrain is where you'll find this. Climbers should limit exposure to overhead gully features and skiers should avoid being under large cliffs. If the wind picks up, expect an immediate increase in activity.

Be very cautious with gully features.Avoid travelling under cliffs that are exposed to sluffing from above.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Valid until: Dec 31st, 2016 2:00PM