Avalanche Forecast

Issued: Jan 21st, 2021 4:00PM

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

Avalanche Canada shorton, Avalanche Canada

Enjoy the clear weather but remember triggering wind slab avalanches is possible on steep open slopes.

Summary

Confidence

High - Confidence is due to a stable weather pattern; little change is expected for several days.

Weather Forecast

THURSDAY NIGHT: Partly cloudy, light northeast wind, treeline temperatures around -6 C.

FRIDAY: Sunny, light north wind, treeline temperatures around -4 C.

SATURDAY: Increasing cloud during the day, light west wind, treeline temperatures around -6 C.

SUNDAY: Cloudy with scattered flurries and 5-10 cm of snow, moderate west wind, treeline temperatures around -5 C.

Avalanche Summary

A steady pulse of storms over the past week caused several widespread natural avalanche cycles. The most recent was on Tuesday with numerous size 1-3 storm slab avalanches at alpine and treeline elevations, especially on wind loaded slopes. Recent MIN reports from the Shames area have some great photos of these avalanches (here and here). In northern parts of the region, these avalanche cycles include some very large avalanches (size 3-4) that stepped down to deeper persistent weak layers.

The snowpack is rapidly gaining strength with the clearing and cooling weather, making the primary concern lingering wind slabs at upper elevations. If you are travelling to northern parts of the region (e.g. Stewart or Ningunsaw), then persistent slabs should be on your radar as well.

Snowpack Summary

Tuesday's storm dumped about 25 cm of snow with strong southwest wind. Since then temperatures have cooled leaving wind slabs in the alpine, unconsolidated powder in sheltered terrain, and a shallowly buried crust below 1000 m. A total of 100-150 cm of settled snow has fallen in January, which has been helping early season weak layers settle and strengthen. Deeper layers have gone inactive in the southern part of the region, however in the northern part of the region (e.g. around Bear Pass and Ningunsaw) there has been regular avalanche activity on weak snow at the bottom of the snowpack.

Terrain and Travel

  • Seek out sheltered terrain where new snow hasn't been wind-affected.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent storm snow is strengthening, but reactive wind slabs could still be found on steep alpine slopes and along ridgetops.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Jan 22nd, 2021 4:00PM