Avalanche Forecast

Issued: Nov 21st, 2015 9:30AM

The alpine rating is below threshold, the treeline rating is below threshold, and the below treeline rating is below threshold. Known problems include Wind Slabs.

Avalanche Canada jlammers, Avalanche Canada

Snowfall and extreme winds are expected to increase the Avalanche Danger. Conservative terrain selection is highly recommended. Forecasters are working with very little field data at this time. Please share your observations on the MIN.

Summary

Weather Forecast

Throughout Sunday we can expect a clearing trend with freezing levels eventually falling to valley bottom. Extreme westerly winds are also expected to shift to moderate and northwesterly as a dry arctic ridge develops for Monday and Tuesday.

Avalanche Summary

A natural avalanche cycle is expected to occur in response to new snow and extreme winds on Saturday. On Sunday, natural avalanche activity is expected to taper-off with forecast cooling and clearing. That said, newly formed wind slabs may remain ripe for human triggering for the next few days.

Snowpack Summary

Reactive wind slabs are expected to form as a result of snow and extreme westerly winds on Saturday. The reactivity of these new wind slabs will likely change with elevation and underlying snowpack structure. Due to limited observations, I have very little confidence in what that underlying structure may be, although faceting and surface hoar development may have occurred on shaded terrain. If you've been in the mountains, please share your observations on our Mountain Information Network.

Problems

Wind Slabs

An icon showing Wind Slabs
The avalanche danger will rise with extreme winds and new snow. Human triggering will remain a concern on Sunday with the potential for wide wind slab propagations.
Be careful with wind loaded pockets. Be aware of wide variation in snowpack depth>Be aware of the potential for wide propagations due to the presence of hard windslabs.>Be alert to conditions that change with elevation.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Nov 22nd, 2015 2:00PM