Avalanche Forecast

Issued: Feb 16th, 2020 5:00PM

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

Avalanche Canada shorton, Avalanche Canada

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As the weather improves the next few days keep in mind there has been a lot of recent snow and triggering avalanches remains possible.

Summary

Confidence

Moderate - A small change in the upper snowpack could dramatically change avalanche conditions.

Weather Forecast

SUNDAY NIGHT: Light flurries with up to 5 cm of new snow, light northwest wind, alpine temperatures drop to -8 C.

MONDAY: Mix of sun and cloud, moderate northwest wind, alpine high temperatures around -6 C.

TUESDAY: Partly cloudy in the morning and sunny in the afternoon, light northwest wind, alpine high temperatures around -6 C.

WEDNESDAY: Sunny, light wind, alpine high temperatures around -6 C.

Avalanche Summary

Recent storm snow has produced widespread sluffing and size 1-2 slab avalanches over the past few days. On Saturday, numerous small (size 1-1.5) skier triggered slabs were reported, primarily in north and east facing wind-loaded roll overs. The slabs were typically 20-40 cm thick. Some thin soft slabs were also reported in sheltered terrain, suggesting storm snow could become reactive as the low density snow settles. Natural avalanche activity will decline as we leave the period of stormy weather, but the storm snow could continue to be reactive to human triggers, especially on slopes that experience daytime warming or sun exposure.

Snowpack Summary

30-60 cm of recent snow is beginning to settle and there is uncertainty about whether it will gain or loose strength in the coming days. There have been reports of this snow starting to be reactive in isolated sheltered terrain where a buried surface hoar layer is 30-60 cm below the surface. A sun crust can be found at similar depths on open south-facing terrain. A widespread rain crust from early February can be found up to 1900 m across the region and to mountain top elevations in some areas, and is now buried 40-80 cm, depending on elevation. The lower snowpack is generally well settled and strong.

Terrain and Travel

  • Start on smaller terrain features and gather information before committing to bigger terrain.
  • Be careful as you transition into wind affected terrain.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.

Problems

Storm Slabs

An icon showing Storm Slabs

30-60 cm of recent snow could be forming unstable slab across a wide variety of terrain. Wind loaded terrain is the most likely place to trigger slabs, but snow in sheltered terrain could also be settling and as a result become more reactive.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Feb 17th, 2020 5:00PM