Avalanche Forecast
Regions: Banff Yoho Kootenay.
Heads up as conditions change overnight and Friday with extreme winds and 10-20 cm in the forecast. Stay in sheltered areas over the next few days as the wind will transport a lot of loose snow into leeward areas and windslabs will develop quickly.
Weather Forecast
A strong westerly flow is established with a Pacific low pressure system off the coast sending moisture our way. Expect 10-20 cm of snow by Saturday morning and extreme winds starting overnight Thursday and into Friday (> 100 km/hr). Temperatures will moderate from the cold snap and we could see highs of -5 on Friday before back to -20 on Saturday.
Snowpack Summary
15-30 cm of snow has fallen over the past week, making for deep powder snow on the surface. This changes on Thurs night with the arrival of strong SW winds, expected to create sensitive windslabs at treeline and in alpine areas as all of that loose snow gets blown around. These slabs may bond poorly to the underlying facets from the cold snap.
Avalanche Summary
No new avalanches were reported or observed in the past 24-hours.
Confidence
Avalanche Problems
Wind Slabs
Windslabs will be building overnight Thursday and all day on Friday. These will be sensitive with the cold facets underneath. Stay away from leeward, loaded terrain. Stick to ridges and high ground.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Watch for surface cracking and stiffer surface layers of snow. Avoid wind loaded terrain.
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2.5
Persistent Slabs
The Dec. 2 crust/facets are down 50-80 cm throughout the region, but we have seen limited avalanche activity on this layer. We believe it only exists as a problem in Kootenay Park, but there is a high degree of uncertainty around this layer.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2.5