Avalanche Forecast

Issued: Jan 22nd, 2024 4:00PM

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

Avalanche Canada dnylen, Avalanche Canada

Email

More snow and warm temperatures will promote storm slab development.

Be cautious in areas where the surface snow feels heavy and cohesive.

Summary

Confidence

Moderate

Avalanche Summary

A natural storm slab cycle was reported on Sunday up to size 2, on all aspects and elevations. All of them failed on a weak layer of facets.

Earlier in the storm on Wednesday, two persistent slab avalanches (size 1 and 2) were remotely triggered by skiers in the Northern Selkirks. These avalanches occurred on north aspects at treeline.

Snowpack Summary

20 to 30 cm of surface snow is now resting on a variety of old snow surfaces including faceted snow, surface hoar and firm wind slabs in open terrain at treeline and above.

Down 60 to 80 cm a crust, facet, and/or surface hoar layer exists.

130+ cm down another surface hoar layer exists that was buried in early December. This seems to be of most concern above 2000 m where a robust crust doesn't exist above it, or in shallow snowpack areas.

Weather Summary

Monday Night

Cloudy with 5-10 cm of snow, south alpine wind 10-50 km/h, treeline temperature around -4 °C.

Tuesday

Cloudy with up to 5 cm of snow, southwest alpine wind 10-40 km/h, treeline temperature around -2 °C, freezing level 1400 m.

Wednesday

Mix of sun and cloud with up to 5 cm of snow, southwest alpine wind 20-40 km/h, treeline temperature around -2 °C, freezing level 1400 m.

Thursday

Cloudy with up to 5 cm of snow, southwest alpine wind 10-30 km/h, treeline temperature around -1 °C, freezing level 1400 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
  • Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.

Problems

Storm Slabs

An icon showing Storm Slabs

New storm slabs have been building with continued snow and warm weather. They are resting on a weak layer of facets and in places surface hoar. This could mean they will be more reactive and slower to bond.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs

Two weak layers of surface hoar and facets exist deeper in the snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Basal facets remain a concern in steep, rocky alpine features with thin-to-thick snowpack transitions.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

2 - 3.5

Valid until: Jan 23rd, 2024 4:00PM