Avalanche Forecast

Issued: Mar 31st, 2023 4:00PM

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

Avalanche Canada zryan, Avalanche Canada

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Head out with a conservative mindset. Friday night's new snow and wind are expected to have formed fresh, reactive wind slabs that may bond poorly to the underlying surface.

Summary

Confidence

Moderate

Avalanche Summary

In the past week, avalanche activity has consisted of small (size 1) natural and skier-triggered wind slabs on north-facing aspects.

This weekend, new snow and the accompanying southwest winds are expected to build fresh, reactive wind slabs in lee-terrain.

Snowpack Summary

5 to 20 cm of new snow will have accumulated by Saturday morning, with deeper deposits in wind-loaded terrain. Below the new snow, a melt-freeze crust exists on all aspects at treeline and below, and on solar aspects to the mountain top. On high north aspects is a mixture of decomposing dry snow and small surface hoar in isolated locations.

The mid-snowpack is generally strong but the lower snowpack is a different story.

A weak layer of sugary facets is still prominent at the base of the snowpack. Small surface avalanches and cornice falls are the most likely things to trigger this layer. However, there remains a concern for human triggering in rocky, shallow, or thin-to-thick snowpack areas at treeline and above.

Weather Summary

Friday night

Cloudy with flurries, trace to 10 cm of accumulation. Alpine temperatures drop to a low of -8 °C. Ridge wind southwest 25 to 60 km/h. Freezing level drops to valley bottom.

Saturday

Mainly cloudy with convective flurries, trace to 5 cm of accumulation. Alpine temperatures reach a high of -6 °C. Ridge wind southwest 20 to 40 km/h. Freezing level rises to 1200 metres.

Sunday

Cloudy with sunny periods and flurries, 5 to 10 cm of accumulation. Alpine temperatures reach a high of -6 °C. Ridge wind light from the southwest. Freezing level rises to 1200 metres.

Monday

Cloudy with sunny periods and isolated flurries. Alpine temperatures reach a high of -5 °C. Ridge wind west 10-30 km/h. Freezing level rises to 1300 metres.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid freshly wind loaded terrain features.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
  • Dial back your terrain choices if you are seeing more than 20 cm of new snow.

Problems

Wind Slabs

An icon showing Wind Slabs

Friday night's new snow and southwest wind will build fresh, reactive wind slabs in lee areas.

In areas that receive greater than 20 cm of new snow, it is possible that a more widespread storm slab problem will exist.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 1st, 2023 4:00PM