Avalanche Forecast

Issued: Feb 14th, 2020 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 shorton, Avalanche Canada

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New snow may be forming reactive slabs at higher elevations, especially on wind affected slopes.

Summary

Confidence

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

Weather Forecast

FRIDAY NIGHT: Scattered flurries with up to 5 cm of new snow, moderate wind from the west, alpine low temperatures around -10 C.

SATURDAY: Mostly cloudy with an 5-10 cm new snow, moderate to strong wind from the west, alpine high temperatures around -10 C.

SUNDAY: Cloudy with isolated flurries, moderate wind from the northwest, alpine high temperatures around -8 C.

MONDAY: Cloudy with flurries, trace to 5 cm of new snow, moderate to strong wind from the northwest, alpine high temperatures around -10 C. 

Avalanche Summary

Preliminary reports from Friday suggest size 1-2 wind slab, storm slab, and dry loose avalanches occurred naturally and some smaller (size 1) human triggered slabs were also reported on steep terrain features. Similar avalanche activity was reported on Thursday. With more wind and snow in the forecast expect wind slabs to continue to be reactive at upper elevations and watch for slab development in steep terrain at all elevations.

Snowpack Summary

15-35 cm of low density snow from Thursday fell with moderate southwest winds formed variable wind slabs in alpine and ridgetop features. Storm slab properties may also be developing in some sheltered locations. Many solar aspects have a sun crust up to 2000 m and small surface hoar has been reported in some isolated areas. 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.

The mid and lower snowpack are generally well settled and strong, but contain two deeper weak layers that we have been tracking since the early part of the season. The late December surface hoar layer, buried 100 to 180 cm deep, is now suspected to be dormant. A facet/crust layer from November exists near the ground in the highest elevations of the region. It remains a limited concern that is likely only able to be triggered with a large load, in high elevation, thin snowpack areas of the Selkirks and the southern half of the region.

Terrain and Travel

  • Be careful as you transition into wind affected terrain.
  • Watch for signs of slab formation throughout the day.
  • Start on smaller terrain features and gather information before committing to bigger terrain.

Problems

Wind Slabs

An icon showing Wind Slabs

Accumulations of new snow over the past week have formed reactive slabs in steep wind affected terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Feb 15th, 2020 5:00PM