Avalanche Forecast

Issued: Feb 17th, 2023 4:00PM

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

Avalanche Canada jpercival, Avalanche Canada

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Storm slab avalanches are present on all aspects. Carefully evaluate the snowpack for slab properties as you move through the terrain and investigate the bond to the crust below.

Avalanches are likely on wind-loaded features in the alpine. Continually assess conditions as they change through the day. Carefully evaluate wind loading as you move through the terrain and investigate the bond of wind slabs to the crust below.

Summary

Confidence

Moderate

Avalanche Summary

On Friday, reports of small (size 1) storm slabs found on all aspects, were triggered during ski cutting at north shore professional operations. Slab properties within the recent storm snow began to present mid-day, as temperatures rose slightly. These slab avalanches ran on a previously well-established melt-freeze crust and were 30 cm in depth.

Snowpack Summary

Overnight Thursday this region observed between 15 and 25 cm of new snowfall. This new snow has accumulated over a variety of surfaces including thin wind slabs in the alpine, small surface hoar in sheltered areas and a breakable freezing rain crust between 1100 m and 1600 m.

A hard crust is found 60 to 80 cm deep. Below this, the mid and lower snowpack is strong and consolidated.

Snowpack depths are reaching 250 cm at treeline.

Weather Summary

Friday Night 

Cloudy with isolated flurries, 1 to 5 cm of accumulation. Ridegtop winds west 30 km/h. Treeline temperatures -6 °C and freezing level to 500 m. 

Saturday

Mainly cloudy with very light isolated flurries, 1 to 5 cm of accumulation. Winds northwest 10 km/h gusting to 50 km/h. Treeline temperatures -2 °C and freezing levels 1200 m. 

Sunday

Cloudy with very light isolated flurries, 1 to 5 cm of accumulation. Winds northwest 40 km/h gusting to 100 km/h. Treeline temperatures -4 °C and freezing levels of 900 m. 

Monday

Cloudy with moderate snowfall, 5 to 15 cm accumulation. Winds northwest 40 km/h gusting 60 km/h. Treeline temperature -3 °C. Freezing level 1000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Carefully evaluate steep lines for wind slabs.
  • Wind slabs are most reactive during their formation.
  • Use increased caution at all elevations. Storm snow is forming touchy slabs.

Problems

Storm Slabs

An icon showing Storm Slabs

Storm snow sits above a hard melt-freeze crust, which may take time to bond. Back off steep slopes until they've had time to stabilize. Be especially cautious where winds have redistributed snow into deep pockets in lees, watch for an increase in slab properties and reactivity.

Expect as northerly winds increase that new winds slabs will begin to form and build on south-aspect slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

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