Avalanche forecast

Sea To Sky

Nov 27, 2017Avalanche Canada
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Archived · expired 9 years ago

Avalanche danger

Tue
Wed
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low

Highlights

Watch for fresh winds slabs left in lee terrain in the wake of Sunday's storm.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–2
    Powerful southerly winds formed wind slabs in lee terrain at higher elevations as the storm ended on Sunday. Continued winds and light snowfall will contribute to the problem and keep slabs touchy over the near term.

Confidence

Moderate -

Weather Forecast

Monday: Cloudy with isolated flurries and a trace of new snow. Light to moderate southwest winds. Freezing level to 1000 metres with alpine temperatures of -7.Tuesday: Periods of snow bringing 15-25 cm of new snow. Moderate to strong southwest winds. Freezing level to 1300 metres with alpine temperatures of -4.Wednesday: Mainly cloudy with scattered flurries and a trace to 5 cm of new snow. Light to moderate southwest winds. Freezing level to 1200 metres alpine temperatures around -5.

Avalanche Summary

Reports from Sunday in the Whistler area showed evidence of a natural avalanche cycle with storm slab and cornice releases ranging from Size 1-2. Activity was focused on northeast to northwest aspects in the alpine. Warm temperatures, heavy precipitation, and high winds all contributed to this natural activity.

Snowpack Summary

Another bout of rain over Saturday night soaked the upper snowpack at all elevations before depositing roughly 5-10 cm of heavily wind affected new snow at higher elevations. In areas where extreme south winds have not scoured it away, approximately 20-30 cm of recent snow overlies the November 23 crust. This 5-10 cm thick crust can be found on all aspects above 1400 m, is present at the surface in windward areas, and overlies a generally rain-saturated snowpack. In high alpine and glaciated terrain a layer of weak sugary crystals that was buried on November 9th exists above a crust near the base of the snowpack. This interface is now buried 150-240 cm deep.

Regions covered