Avalanche Forecast

Issued: Mar 26th, 2020 4:00PM

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

Avalanche Canada astclair, Avalanche Canada

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Recent snow and wind have created heightened avalanche conditions at higher elevations.

Summary

Confidence

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

Weather Forecast

Thursday night: Cloudy, scattered flurries with up to 5 cm of accumulation, moderate to strong southwest wind, freezing level dropping to 900 m, alpine temperatures reach -6 C.

Friday: Cloudy, scattered flurries with trace accumulations, moderate southwest wind, freezing level climbing to 1500 m in the afternoon, alpine temperatures reach -3 C.

Saturday: Cloudy, 5-10 cm of new snow, moderate southwest wind, freezing level climbing to 1600 m in the afternoon, alpine temperatures reach -2 C.

Sunday: Cloudy, 5-10 cm of new snow, moderate southwest wind, freezing level climbing to 1500 m in the afternoon, alpine temperatures reach -3 C.

Avalanche Summary

No recent avalanches have been reported, but mountain travel and field observations have been very limited over the past few days. Last week there were many wet loose avalanches and some large glide slabs, but cooler weather and new snow has probably fresh new wind slabs the main concern.

Snowpack Summary

Recent snowfall amounts have been highly variable with some areas receiving 15-25 cm and adjacent valleys getting as little as 0-5 cm. Some of the heavier accumulations have been in the south part of the region. Periods of moderate southwest wind may have drifted the new snow into stiffer slabs at upper elevations. The new snow covers a variety of previous snow surfaces including crusts, warm snow, and wind-affected snow. It may also sit above some small surface hoar on shaded, sheltered slopes. Overall, there is some uncertainty about how well the new snow will bond to these interfaces.

Northern parts of the region have had a deep instability lingering at the base of the snowpack for most of the season, however this layer has gained strength over the past month (with the last reported avalanche on Feb 17).

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Closely monitor how the new snow is bonding to the old surface.

Problems

Wind Slabs

An icon showing Wind Slabs

Recent snow and moderate southwest wind may have formed unstable slabs in localized areas. Slab formation is most likely in the southern part of the region that has received more recent snow. There is uncertainty about how well these slabs will bond to underlying interfaces.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 27th, 2020 5:00PM