Avalanche Forecast

Issued: Mar 11th, 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 zryan, Avalanche Canada

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Be cautious as you enter wind-affected terrain, recently formed wind slabs are expected to bond poorly to the slick underlying crust.

Avoid overhead cornices, especially during periods of strong solar radiation.

Summary

Confidence

Moderate

Avalanche Summary

On Thursday, explosive control targeting cornices produced size 1-1.5 avalanches that did not pull slabs on the slopes below.

On Friday, fresh wind slab formation was observed as moderate to strong northeast wind redistributed the surface snow into immediate lees, as seen in this MIN report from the Fernie area.

Snowpack Summary

5 to 10 cm of low-density new snow has been redistributed by northeast winds into pockets of wind slab in exposed areas. This new snow overlies hard wind-affected surfaces in open areas, a sun crust on steep solar aspects, and facetted snow in sheltered areas.

The mid-snowpack is generally well-settled. The lower snowpack includes a layer of weak sugary crystals near the ground. These facets are slowly gaining strength and have not produced recent avalanche activity. We continue to track the layer and watch for any signs that it could wake up and produce very large avalanches.

Weather Summary

Saturday night

Clear periods with isolated flurries. Alpine temperatures drop to a low of -8 °C. Ridge wind light from the southwest. Freezing level at valley bottom.

Sunday

A mix of sun and cloud with isolated flurries. Alpine temperatures reach a high of -2 °C. Ridge wind 15 to 40 km/h from the southwest. Freezing level rises to 1300 meters.

Monday

Cloudy with mixed precipitation, 10-15 cm of new snow accumulation at upper elevations. Alpine temperatures reach a high of 2 °C. Ridge wind 30 to 70 km/h from the southwest. Freezing level rises to 1900 meters.

Tuesday

A mix of sun and cloud with flurries. Alpine temperatures drop to a low of -4 °C. Ridge wind 20 to 50 km/h from the southwest. Freezing level 1300 meters.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be especially cautious as you transition into wind affected terrain.
  • Wind slabs may be poorly bonded to the underlying crust.
  • Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.

Problems

Wind Slabs

An icon showing Wind Slabs

Friday's northeast wind and 5-15 cm of new snow are expected to have formed small but reactive wind slabs most likely found on southwest-facing slopes. Wind slabs may bond poorly to the underlying crust.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Mar 12th, 2023 5:00PM