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 -10 C.

MONDAY: Light flurries with up to 5 cm of new snow, some sunny break possible, light northwest wind, alpine high temperatures around -8 C.

TUESDAY: Sunny with a few clouds, light northwest wind, alpine high temperatures around -8 C.

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

Avalanche Summary

Steady snowfall and wind over the past week has resulted in regular storm slab, wind slab, and dry loose avalanche activity. On Saturday size 1-2 slab avalanches were triggered naturally and by riders on a variety of aspects and elevations. The avalanches were typically 20-40 cm thick, but one 60 cm thick slab release on a surface hoar layer on a west aspect in the trees. 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.

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 buried crust from the early February rain storm is now 50-100 cm below the surface. In most areas the snow has bonded to this crust, but in areas where the crust is shallowly buried it could be slower to bond. 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 carefull around freshly wind loaded features.
  • 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 at sheltered lower elevations could also be settling and forming more reactive slabs in steep terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2.5

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