Avalanche Forecast

Issued: Feb 9th, 2017 3:00PM

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

mike.koppang, Alberta Parks

Kananaskis.

Strong winds, new snow and warming temps are creating new storm slabs that are sitting on top of an already weak snowpack. Good time to ski at a hill!

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Friday

Weather Forecast

An additional 10-20cm of snow is forecast to fall over the next 24hrs with strong SW winds and seasonal temperatures. Freezing levels are forecast to remain around 1600m. We are seeing a warming trend moving into next week.

Avalanche Summary

No new natural avalanche activity was observed on Thursday but visibility was obscured all day.

Snowpack Summary

Snow began falling later in the afternoon on Thursday as well as westerly winds and temperatures began to increase. Forecasters were running into storm slabs up to 30cm thick in most open areas at all elevation bands. The more deeply buried weak facetted base is also widespread in the region and any avalanche that initiates in the upper snowpack is likely to step down to this weak base and involve the entire winters snowpack. Winds winds and snow expected to continue over the next 24hrs, we only expect these storm slabs to become thicker and more reactive.

Problems

Storm Slabs

Recent snow combined with strong SW winds and warmer temps on Thursday have created widespread storm slabs in all open areas. These slabs are more of a settlement slab in below treeline areas.

If triggered the storm slabs may step down to deeper layers resulting in large avalanches.Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.

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

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2

Wind Slabs

Buried wind slabs are widespread at Treeline and above. A natural avalanche cycle is expected to start again on thursday evening and continue into friday.

Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

2 - 3

Deep Persistent Slabs

The basal layers remain exceptionally weak. The potential for an avalanche initiated in the upper snowpack to step down to deep instability and cause a very large avalanche is a concern.

Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Feb 10th, 2017 2:00PM