Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Jan 9th, 2022–Jan 10th, 2022

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.

Regions

Banff Yoho Kootenay.

Evidence of a wind slab cycle was evident on Sunday. Human triggering remains likely. The Mt Whymper and Simpson avalanche closure zones are CLOSED on Mon Jan 10 for avalanche control.

Weather Forecast

Wx models suggest there is little respite in the wind, which will generally remain in the strong range from the W/SW for the next few days. Temperatures will be slightly warmer than seasonal but the freezing level should remain below surface. A small to moderate amount of new snow (10-20cm) is expected late on Tuesday.

Snowpack Summary

Strong wind from the SW is redistributing available snow into lee areas in both the alpine and treeline. These slabs may bond poorly to the underlying facets from the cold snap. The Dec 2 crust/facet interface is down 60-100 cm, and the snowpack is very faceted in shallower areas.

Avalanche Summary

Two size 2 wind slab avalanches  were observed in the Bow Summit area on Sunday. Also, Massey's near Field, went size 2.5 and poured over the ice climb in the past 24 hours. Lake Louise patrollers triggered a size 2 wind slab with explosives. Please see yesterdays MIN report of the avalanche that occurred on the Dec 2 crust in the Simpson paths.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Tuesday

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.