Avalanche forecast

South Coast

Mar 1 – 2, 2023Avalanche Canada
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Avalanche danger

Fri
Sat
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable
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Highlights

Up to 70 cm of storm snow has fallen since last weekend! Storm slab reactivity is expected to persist for longer than typical, due to the weak surface they are sitting on. Human triggering remains likely.

Avalanche problems

  • Loose Dry

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1–1.5

    If the recent storm snow lacks cohesion, dry loose avalanches will be likely from steep terrain features at all elevations.

  • Storm Slabs

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

    Another 20 cm fell overnight Monday adding to last weekend's 50 cm of storm snow. The recent storm slab averaging 30-60 deep and up to 100 cm deep in wind-loaded areas may have bonded poorly to the underlying surface.

    Storm slab reactivity is expected to persist for longer than is typical, particularly in areas where slabs are sitting on a weak layer of facets and/or a crust.

Confidence

Low

Avalanche Summary

No recent avalanche activity reported as of Tuesday morning.

On Sunday, a widespread natural cycle occurred throughout the region. Reports came in of very touchy human-triggered storm slabs (size 1-2) averaging 30-60 cm deep and up to 100 cm deep in wind-loaded areas.

Storm slab reactivity is expected to persist for longer than is typical due to the weak surface they are sitting on.

Check out last Friday's North Shore Snowpack Update for a picture of the unusual snowpack setup leading into last weekend's storm.

Snowpack Summary

Up to 20 cm of new snow overnight Monday adds to last weekend's storm snow bringing totals of 50-70 cm down to the valley bottom. This new snow has bonded poorly to the underlying surface formed by recent wind and cold temperatures. The old snow surface consists of weak faceted snow, old hard wind slabs, and a crust between 1100 and 1600 m.

The mid and lower snowpack is well-settled, strong, and consolidated.

Snowpack depths are reaching 250 cm at treeline.

Weather Summary

Tuesday Night

Clear periods. Treeline temperatures -4 °C. Ridge wind southeast 10-20 km/h. Freezing level valley bottom.

Wednesday

Cloudy with flurries, 5-10 cm of accumulation Treeline temperatures reach a high of -4 °C. Southwest wind 20 km/h and freezing level valley bottom.

Thursday

Snow amounts 10-20 cm. Ridgetop wind 35-55 km/h from the west. Treeline temperatures reach a high of -5 °C. Freezing level valley bottom.

Friday

Cloudy with sunny periods and isolated flurries. Treeline temperatures near -5 °C. Ridge wind southwest 40 km/h gusting to 70 km/h. Freezing level 500 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
  • Closely monitor how the new snow is bonding to the crust.
  • Keep your guard up at lower elevations. Storms slabs have been reactive at all elevations.
  • Avoid terrain traps where the consequence of any avalanche could be serious.
  • Loose avalanches may start small but they can grow and push you into dangerous terrain.

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