Avalanche forecast

Sea To Sky

Mar 17 – 18, 2025Avalanche Canada
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Avalanche danger

Wed
Thu
Alpine
3 · Considerable
Treeline
2 · Moderate
Below
2 · Moderate

Highlights

Changing conditions are expected and a complex snowpack is hidden under the storm snow.

Carefully manage your exposure to overhead hazards during periods of sun.

Avalanche problems

  • Wind Slabs

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

    Recent snow and wind have created fresh wind slabs. Use caution as you transfer into wind-affected terrain, as these slabs are still reactive to riders.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–4

    A weak layer from early March is now 120 to 175 cm deep with January and February layers buried 150 to 250 cm. There's still uncertainty about avalanches stepping down to these layers, potentially triggering very large avalanches.

  • Loose Wet

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

    Wet loose avalanches will be likely on steep sun-exposed slopes. Avoid overhead hazard from steep sunny faces during the warmest parts of the day.

Confidence

Moderate

Avalanche Summary

Storm and wind slabs were reactive to skier's traffic on alpine lee and cross-loaded features, producing avalanches up to size 1.5, with good propagation along ridge crests and uphill steep terrain.

Fast-running sluffs were easily triggered by riders on steep northerly slopes, producing small loose dry avalanches throughout the region.

Thanks for sharing your observations via the MIN if you are going out into the backcountry.

Snowpack Summary

The region received 10 to 20 cm this past weekend, totaling 120 to 175 cm of recent storm snow, which has settled out rapidly. Southerly winds have formed deeper deposits of wind-transported snow into lee features.

Under it, a weak layer formed in early March that consists of a crust on all aspects except high north-facing slopes and facets or surface hoar in some areas.

Weak layers formed in mid-February and late January are now buried 150 to 250 cm deep. We suspect these layers have mainly healed, but observations have been limited by stormy conditions.

Below this, the snowpack is well-settled and strong.

Weather Summary

Monday Night

Partly cloudy with isolated flurries. 20 to 30 km/h northwest ridgetop wind. Treeline temperature -8 °C. Freezing level valley bottom.

Tuesday

A mix of sun and clouds. 20 to 40 km/h south ridgetop wind. Treeline temperature -3 °C. Freezing level 1000 m.

Wednesday

Partly cloudy with 5 to 10 cm of new snow. 50 to 70 km/h southeast ridgetop wind. Treeline temperature -2 °C. Freezing level 1200 m.

Thursday

Cloudy with 15 to 20 cm of new snow. 30 to 50 km/h south ridgetop wind. Treeline temperature -2 °C. Freezing level 1200 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Back off slopes as the surface becomes moist or wet with rising temperatures.
  • Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.
  • Cornice failures could trigger large and destructive avalanches.

Regions covered