Avalanche Forecast

Issued: Feb 7th, 2022 4:00PM

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

Aaron Beardmore,

Email

The recently introduced persistent slab problem dated on Jan 30 is developing. In Yoho it is located 30-40cm down. This depth will vary depending on location. Dig down to test the reactivity and register the depth before committing to your line.

Summary

Weather Forecast

The next few days will bring unsettled weather and small amounts of snow. Notably, the wind will stay elevated in the strong range from the west for the next few days. Also, on Thursday the freezing level could rise to 1700m. In summary, expect a warm, windy and snowy few days.

Snowpack Summary

Strong winds continue to redistribute the 20-30 cm of recent snow at upper elevations creating wind slab on lee slopes. At tree line and below the recent storm snow is beginning to develop into a slab, which overlays the Jan 30 surface hoar and sun crust. This interface is found 30 to 40cm down. Shallow snowpack areas remain weak and faceted.

Avalanche Summary

Lake Louise patrollers knocked out a few hard slabs to size 1 with explosives today. Sunshine saw very little in the way of avalanches. There is a report of a size 2 avalanche on Dolomite peak that came from an alpine start zone to the top of the fan, approximately size 2.

Confidence

Due to the number and quality of field observations on Monday

Problems

Wind Slabs

An icon showing Wind Slabs

As you approach treeline, expect to encounter slab development. Today, the wind was redistributing snow well into tree line. Take the time to investigate what the recent snow is sitting on and how it is bonding.

  • Caution on open steep slopes at treeline that have been exposed to wind loading.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

This layer exist as surface hoar in sheltered areas and sun crust on steep southerly aspects 30 to 40cm down. We have only observed a few avalanche on this interface so far. As more slab develops over this layer, we expect it to become more reactive.

  • Dig down to find and test weak layers before committing to a line.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Feb 8th, 2022 4:00PM