Avalanche forecast

South Coast

Mar 15 – 16, 2021Avalanche Canada
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Avalanche danger

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

Highlights

A warming trend will weaken cornices and snow on sun-exposed slopes during the heat of the day. Wind slabs may linger at high elevations.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Wind slabs could linger in steep, lee terrain features at high elevations. The wind howled from the south to east, so expect to find them predominantly on west to north aspects.

  • Cornices

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–3

    Cornices are large and looming. A warming trend and sunny skies will weaken cornices, increasing the likelihood of them releasing naturally or from the weight of a person.

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Wet loose avalanche activity is most likely above around 1200 m, as the recent snow moistens from daytime warming. Use caution on sun-exposed slopes during the heat of the day.

Confidence

High -

Weather Forecast

MONDAY NIGHT: Partly cloudy, 10 km/h northwest wind, treeline temperature -4 C.

TUESDAY: Mix of sun and cloud, 10 km/h west wind, treeline temperature -2 C, freezing level rising to 1000 m.

WEDNESDAY: Mostly cloudy, 20 to 40 km/h south wind, treeline temperature 0 C, freezing level 1500 m.

THURSDAY: Cloudy with snow or rain, accumulation 10 to 20 cm, 40 to 60 km/h south wind, treeline temperature 0 C, freezing level 1400 m.

Avalanche Summary

We haven't yet received word of avalanche activity from Sunday's storm, but it is likely that storm slabs and wind slabs were triggerable on Sunday and Monday. Looking forward, wind slabs could still be triggered by riders in steep terrain at high elevations. Sun-exposed slopes and cornices will weaken with daytime warming.

Snowpack Summary

Wind slabs may linger in steep, lee terrain features at treeline and alpine elevations from Sunday's 20 cm of snow with strong south to east wind. On sun-exposed slopes above 1200 m, this recent snow will weaken with daytime heating, particularly on sun-exposed slopes. Below 1200 m, a wet snowpack or a hard melt-freeze crust will be found. Along ridgelines, cornices are large and will weaken with daytime heating.

Terrain and Travel

  • Carefully evaluate steep lines for wind slabs.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
  • A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.
  • Extra caution is needed around cornices under the current conditions.

Regions covered