Avalanche Forecast

Issued: Apr 17th, 2023 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs.

Avalanche Canada mconlan, Avalanche Canada

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Wind slabs may linger in lee terrain features, which could step down to a buried layer and form large avalanches.

Summary

Confidence

Moderate

Avalanche Summary

We haven't received any reports of recent avalanche observations. The most recent avalanches occurred about a week ago on the facet layer described in the Snowpack Summary (e.g., this MIN).

Snowpack Summary

Around 10 to 20 cm of snow fell over the past couple days with strong southerly wind, likely forming wind slabs in lee terrain features. The snow overlies a hard melt-freeze crust at treeline elevations and below. In the alpine, the snow overlies a variety of old surfaces including dry snow and hard wind slabs on northerly aspects and a crust or wind-pressed snow on southerly aspects.

A layer of facets and a crust from early April is buried up to 60 cm at treeline and alpine elevations.

The base of the snowpack remains faceted and weak. We haven't received any notes of recent avalanche activity on this layer, but the concern remains for steep and rocky slopes with a thin snowpack.

Weather Summary

Monday Night

Mostly cloudy with intermittent snowfall, accumulation 2 to 5 cm, 20 km/h south wind, treeline temperature -7 °C.

Tuesday

Mix of sun and cloud with afternoon snowfall, accumulation 2 to 5 cm, 20 km/h south wind, treeline temperature -6 °C, freezing level to 1300 m.

Wednesday

Mix of sun and cloud with isolated flurries, 10 km/h south wind, treeline temperature -4 °C, freezing level to 1500 m.

Thursday

Clear skies with no precipitation, 10 km/h southwest wind, treeline temperature -2 °C, freezing level to 1700 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Approach lee and cross-loaded slopes with caution.
  • Use ridges or ribs to avoid areas of wind loaded snow.
  • Remote triggering is a concern, watch out for adjacent and overhead slopes.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs may remain in lee terrain features from recent snow and strong southwest wind. Small avalanches could step down to a layer of facets and a crust buried 60 cm that could result in large avalanches.

Aspects: North, North East, East, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 18th, 2023 4:00PM