Avalanche forecast

South Rockies

Feb 12 – 14, 2021Avalanche Canada
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Avalanche danger

Sun
Mon
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

There is a potential for a localized uptick in north east wind tomorrow so watch for newly formed and reactive wind slabs as you transition into wind affected terrain. The consequences of even small accidents and injuries in this cold weather requires conservative trip plans.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–2.5

    With loose snow to redistribute, wind is a major driver of avalanche hazard for now. Use caution around ridges, cornices, and loaded features. In steeper sheltered terrain, be cautious of dry-loose avalanches and mindful of sluffing.

    A weak interface may exist in some locations approximately 60 cm down and could reach its threshold with wind stiffened snow, initiating a deeper slab. At this point, this interface seems spotty through the region and hasn't been as reactive as in the Lizard-Flathead region. However, it is something to keep on your radar. 

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

FRIDAY NIGHT - Some cloud / light easterly wind / low of -26

SATURDAY - Increasing cloud / light north east wind / alpine high -20

SUNDAY - Partly cloudy / light southerly wind / highs of -14

MONDAY - Overcast, trace of new snow / light west wind / -12

Avalanche Summary

Skiers triggered a large (size 2.5) avalanche on a south facing slope in K-Country (forecast region to the north of us) yesterday. Facets over an old sun crust may have played a role. You can read the MIN report here.

Neighbouring forecast regions reported a couple of cornice falls recently, as well as a natural wind slab out of extreme terrain. Ski cuts have been producing small avalanches avalanche in reverse loaded terrain. 

On Friday there was a report of a size 2 explosives triggered wind slab avalanche, as well as a few size 1 human triggered dry loose avalanches. There was also a report of several natural avalanches, potentially up to size 3, a MIN report outlining these can be found here.

Snowpack Summary

Variable winds have redistributed loose snow developing slabs in lee and open features.

A weak interface may exist in some locations approximately 60 cm down and could reach its threshold with wind loading, initiating a deeper slab. At this point, this interface seems spotty through the region and hasn't been as reactive as in the Lizard-Flathead region. However, it is something to keep on your radar! You should dig down and investigate this interface before committing to bigger lines.

In most places 30-60 cm loose snow and soft slab overlies a handful of surfaces: wind affected snow at upper elevations and exposed terrain, softer snow in sheltered areas, and a crust on steep, solar slopes and below 1600-1900 m. 

A solid mid-pack sits above deeply buried decomposing crust and facet layers near the bottom of the snowpack (80-150 cm deep). Though unreactive under the current conditions, steep rocky slopes and shallow snowpacks should still be approached with caution.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Avoid areas where the snow feels stiff and/or slabby.
  • Carefully evaluate big/extreme terrain features before committing to them, it's not full "go" time yet.
  • Be carefull with sluffing in steep terrain, especially above cliffs and terrain traps.

Regions covered