Avalanche Forecast

Issued: Jan 30th, 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 lbaker, Avalanche Canada

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Watch for pockets of stiff wind slab at upper elevations from recent winds. These slabs may be in atypical areas due to reverse-loading.

Avoid shallow areas where the snowpack transitions from thick to thin and triggering deep weak layers is more likely.

Summary

Confidence

Moderate

Avalanche Summary

On Sunday, a few natural, size 1 to 1.5, wind slab avalanches were reported at higher elevations.

On Saturday several thin wind slabs, up to size 1.5, were reported to be reactive to natural and human triggers.

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

Snowpack Summary

15 cm of storm snow has been redistributed by variable winds in the alpine and at treeline. New snow sits over a crust on southerly slopes, previously wind affected surfaces in exposed areas and over a layer of surface hoar in sheltered areas.

A crust and facet layer from mid January, 2 to 15 cm thick at treeline sits 50 to 90 cm deep. Where it's thickest, it caps the settled and consolidated mid-snowpack.

The lower snowpack contains weak and facetted grains from November. The total snowpack depth ranges between 120 and 250 cm.

Weather Summary

Monday Night

Mainly cloudy with isolated flurries. Moderate northwesterly winds gusting 40 km/h. Alpine high of -17°C.

Tuesday

Cloudy with sunny periods and isolated flurries, trace accumulations. Westerly ridgetop winds 40 km/h. Alpine high of -13°C.

Wednesday

Cloudy with sunny periods and isolated flurries, trace accumulations. Westerly ridgetop winds 40 km/h. Alpine high of -8°C.

Thursday

Sunny with cloudy periods. Southwesterly ridgetop winds 40-60 km/h. Alpine high of -5°C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Approach lee and cross-loaded slopes with caution.
  • 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

Look for wind-affected snow on all aspects in exposed treeline areas and in the alpine. Variable moderate winds have redistributed 15 cm of storm snow into stubborn wind slabs at higher elevations. Watch for reverse loading and cross-loading in unusual spots.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Faceted grains make up the lower snowpack and are gaining strength very slowly. Although deep persistent slab avalanches have not been reported in the region for some time there is concern that this layer remains an active avalanche problem in the northern, data-sparse parts of the region. In these areas, this layer could still be triggered with a heavy load, like a cornice fall, machine trigger, or in areas with a thinner snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 3.5

Valid until: Jan 31st, 2023 4:00PM