Avalanche Forecast

Issued: Feb 5th, 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 and Deep Persistent Slabs.

Avalanche Canada bchristie, Avalanche Canada

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Evaluate snow conditions as you transition into open terrain features, and be on the lookout for signs of instability like shooting cracks. Stiff, wind deposited snow can be expected to avalanche under the weight of a rider. Also, moist, heavy snow may slide easily on steep slopes. Especially where it is sitting on top of lighter, fluffy snow.

Summary

Confidence

Moderate

Avalanche Summary

On Saturday, east of Fernie, a couple of small to large natural and rider triggered avalanches were reported that involved cornices. See the MIN report for more information.

Natural and rider-triggered (size 1 to 1.5) wind slabs have been recently reported at treeline and alpine elevations. This MIN report from the South Rockies field team is a good example of terrain where wind slabs are more likely to be triggered.

Looking forward, riders could trigger small wind slabs in lee terrain features from the recent snow and sustained southwest wind.

Please continue to share any observations or photos on the Mountain Information Network.

Snowpack Summary

Possible 5-10 cm of moist snow on the surface.

10 to 15 cm of storm snow from late last week was redistributed by moderate to strong winds which developed wind slabs at treeline and alpine elevations. This overlies previous wind slabs that may still be reactive, or a melt-freeze crust below 1900 m

The mid-pack is consolidated in the Lizard Range with a robust melt-freeze buried 70 to 90 cm.

Outside of the Lizard Range, the snowpack is shallower and more faceted. In these areas, deep weak layers formed early season are slowly gaining strength but are still a concern, especially in steep rocky terrain features.

Weather Summary

Sunday Night

Clearing overnight. No new snow expected. Moderate northwest ridgetop wind. Treeline temperature around -3 ºC.

Monday

Clear in the morning, increasing clouds through the day. No new snow expected. Moderate southwest ridgetop wind, trending to strong at higher elevations. Treeline temperature around -2 ºC.

Tuesday

Cloudy. 5-12 cm of snow expected, on the higher end in the north of the region. Moderate southwest ridgetop wind, trending to strong at higher elevations. Treeline temperature around -5 ºC.

Wednesday

Mostly cloudy. 5-15 cm of snow expected, on the higher end in the south of the region. Moderate west ridgetop wind. Treeline temperature around -7 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Approach lee and cross-loaded slopes with caution.
  • Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
  • Watch for unstable snow on specific terrain features, especially when the snow is moist or wet.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Problems

Wind Slabs

An icon showing Wind Slabs

10 to 20 cm of recent snow coupled with southwest wind could continue to build wind slabs in lee terrain features. Look for signs of instability like shooting cracks as you approach open terrain features.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

A layer of faceted grains near the base of the snowpack remains on the radar for areas of this region where the snowpack is shallow and where a hard melt-freeze crust formed around Christmas doesn't exist. Deep persistent slab avalanches have not been reported in the region for some time, however, the weak snowpack structure in these shallow areas may still be triggered with a heavy load.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2.5 - 3.5

Valid until: Feb 6th, 2023 4:00PM