Avalanche Forecast

Issued: Jan 16th, 2020 4:00PM

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

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Pay attention to wind affected snow in open terrain where triggering avalanches is most likely.

Summary

Confidence

Moderate - Uncertainty is due to limitations in the field data.

Weather Forecast

THURSDAY NIGHT: Light flurries, moderate wind from the southwest, alpine temperatures drop to -20 C.

FRIDAY: Light flurries with some sunny breaks, light wind from the southwest, alpine high temperatures around -15 C.

SATURDAY: Scattered flurries with up to 5 cm of snow, moderate wind from the south, alpine high temperatures around -12 C.

SUNDAY: Light flurries with 5-10 cm of snow, strong wind from the south, alpine high temperatures around -6 C.

Avalanche Summary

Avalanche activity has quieted down over the past few days, but light snowfall and southwest gusts are likely refreshing the wind slab problem. Last weekend there were notable signs of a reactive persistent slab problem including large whumpfs and a large snowmobile triggered avalanche in the neighbouring Clemina area (see the MIN report). The surface hoar layer responsible for this problem has been harder to find since then, but could still potentially produce large avalanches in certain sheltered slopes around treeline and could perhaps re-activate with a sudden change in weather.

Snowpack Summary

Surface conditions are variable due to cold temperatures and shifting wind directions over the past few days, but expect to find fresh wind slabs on open north and east facing slopes. The main concern over the past week has been a layer of surface hoar buried 60-120 cm beneath the surface, but recent observations suggest this layer has trended towards being less reactive under the current conditions.

Terrain and Travel

  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.

Problems

Wind Slabs

An icon showing Wind Slabs

Triggering wind slab avalanches is possible in steep open terrain at higher elevations, especially near ridgetops.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A layer of surface hoar buried 60-120 cm below the surface could still be reactive to human triggering in clearings around treeline.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Unlikely

Expected Size

2 - 3

Valid until: Jan 17th, 2020 4:00PM