Avalanche Forecast

Issued: Jan 20th, 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.

Avalanche Canada mconlan, Avalanche Canada

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Newly formed slabs will likely remain reactive to riders.

Summary

Confidence

High - We have a good understanding of the snowpack structure and confidence in the weather forecast

Weather Forecast

THURSDAY NIGHT: Cloudy with snowfall, accumulation 2 to 5 cm, 50 km/h west wind, alpine temperature -5 C, freezing level 800 m.

FRIDAY: Cloudy with early-morning snowfall, accumulation 2 to 5 cm, 60 km/h west wind, alpine temperature -3 C, freezing level 1100 m.

SATURDAY: Mix of sun and cloud with intermittent snowfall, accumulation 1 to 3 cm, 50 km/h southwest wind, alpine temperature 0 C, freezing level 2500 m.

SUNDAY: Mostly cloudy with no precipitation, 40 km/h west wind, alpine temperature -3 C, freezing level 1200 m.

Avalanche Summary

Cloudy conditions limited visibility on Thursday, but it is expected that some natural wind and storm slab avalanches released during Wednesday night's storm.

Looking ahead, wind slabs will likely remain reactive to riders on Friday.

Snowpack Summary

Around 10 to 20 cm of snow accumulated on Thursday. The snow fell with strong southwest wind, which likely formed wind slabs in terrain exposed to the wind. Below around 1200 m, the snow fell on a melt-freeze crust.

Two weak layers may exist. First is a layer of surface hoar that may be found around 30 cm deep. To date, this layer has produced avalanches in the centre and north of the region and not the south, though it has been found in the south. Next, a widespread layer of faceted grains is found around 30 to 60 cm deep, which formed during the cold spell in late December and early January. These layers have been most reactive in the central portion of the region.

In thin snowpack areas, the base of the snowpack is composed of weak faceted grains around various melt-freeze crusts, which are considered dormant at this time.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Avoid freshly wind loaded terrain features.
  • Make observations and assess conditions continually as you travel.
  • Be aware of the potential for large avalanches due to the presence of buried surface hoar.

Problems

Wind Slabs

An icon showing Wind Slabs

Around 10 to 20 cm of recent snow fell with strong southwest wind, which is forecast to continue into Friday. Expect to find touchy wind slabs in lee terrain features in wind-exposed terrain. It is possible you could also find storm slabs in steep terrain sheltered from the wind. These slabs may be particularly touchy where they sit on surface hoar crystals.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 21st, 2022 4:00PM