Avalanche Forecast

Issued: Jan 28th, 2024 4:00PM

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

Avalanche Canada GS, Avalanche Canada

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Very warm temperatures, rain to 1900 m and strong winds are causing an avalanche cycle. Avalanche control is planned on Monday for the Sunshine Road and the Trans-Canada Highway from the BC/AB border to Field. Mt. Bourgeau, Mt. Stephen and Mt. Field are closed on Monday. The next few days will be good days to avoid the backcountry.

Summary

Confidence

High

Avalanche Summary

Both ski areas (Sunshine and Lake Louise) reported small avalanches from ski cutting but nothing significant. Bosworth 3 (above the highway) released a size 2.5 natural in the last 12 hours, stopping in the trees. Otherwise, observations have been very limited due to poor visibility.

Snowpack Summary

Rain has saturated the snowpack up to 1900 meters and wind has created windslabs in most alpine/treeline areas. These slabs are releasing on two weak layers in the upper snowpack: 1) facets from the cold snap 10-30cm deep, and 2) surface hoar or sun crust below the facets 30-50cm deep. The lower snowpack is comprised of weak facets and depth hoar. Overall this is a weak snowpack that should not be trusted.

Weather Summary

A strong westerly flow is delivering a serious atmospheric river to the BC coast which will spike temperatures and freezing levels in the Rockies. Expect freezing levels to reach 2500 m on Monday accompanied by strong winds and surprisingly, minimal precipitation. Only a few cm of snow or a few mm of rain is expected. These warm temperatures will persist until next weekend.

Terrain and Travel Advice

  • Avoid areas where the snow feels stiff and/or slabby.
  • The likelihood of deep persistent slab avalanches will increase with each day of warm weather.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

Problems

Loose Wet

An icon showing Loose Wet

Rain to 1900 m and warm temperatures have saturated the snowpack below treeline, and this has resulted in widespread sluff and slush avalanches happening in gullies. The snowpack below treeline will have no strength and will not recover overnight until the temperatures cool.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Very Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

Recently formed windslabs sit on facets produced during the cold snap, as well as surface hoar/suncrust found below these facets. This is an unstable combination and we've seen evidence of multiple avalanches on this layer over the last week. Avoid steep, open slopes until it cools off again.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The base of the snowpack consists of weak facets, depth hoar, and the overlying crust in the midpack continues to break down. Use caution in steep terrain, large planar slopes, and thin to thick areas where initiating these slabs would be more likely.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1.5 - 2.5

Valid until: Jan 29th, 2024 4:00PM