Avalanche forecast

South Coast

Dec 20 – 21, 2017Avalanche Canada
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Archived · expired 9 years ago

Avalanche danger

Fri
Sat
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
1 · Low
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Highlights

On the North Shore the new snow has been showing signs of poor bonding to the recent crust surface. Further north in alpine terrain watch for fresh wind slabs on lee-loaded and cross-loaded slopes.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2
    Tuesday's storm snow is now being redistributed by wind at upper treeline and alpine elevations and lies on a widespread melt-freeze crust that has been showing poor signs of bonding.

  • Loose Dry

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2
    Storm snow has been showing signs of poor bonding to the most recent crust.

Confidence

High - The weather pattern is stable

Weather Forecast

THURSDAY: Mainly cloudy, flurries. Accumulation 5-10 cm. Ridge wind light to moderate from the west. Temperature -3. Freezing level 500 m. FRIDAY: Mix of sun and cloud, light flurries. Accumulation trace. Ridge wind light from the north. Temperature -3. Freezing level 500 m.SATURDAY: Mostly sunny. Ridge wind light from the east. Temperature -6. Freezing level surface.

Avalanche Summary

On Tuesday a few natural, loose dry avalanches were observed in the recent storm snow. Ski cutting also produced storm slab and loose dry avalanches to Size 1 running far on the December 18th crust. And explosive control work produced storm slab avalanches up to Size 1.5, propagating about 40 m wide with crowns 20-25 cm deep, failing on the December 18th crust.

Snowpack Summary

Since Monday, the region has received 20-30 cm of storm snow on top of the most recent December 18th melt-freeze crust which formed following Sunday's rain event to upper elevations. Below this crusts lies 20 cm of wet snow which appears to be well bonded to the lower December 16th crust. Below this second crust the snowpack is well settled to ground. Snowpack depths are about 125 cm at 1100 m elevation, with many early season hazards present at lower elevations.

Regions covered