Avalanche Forecast

Issued: Feb 3rd, 2023 4:00PM

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

Avalanche Canada LP, Avalanche Canada

Email

Wind and cornice triggered natural windslab avalanches have been occurring throughout the week in the alpine. This may continue with the wind and light flurries forecasted through the weekend.

Summary

Confidence

Moderate

Avalanche Summary

Lake Louise forecasters triggered several size 1-1.5 windslabs with explosives. Sunhine forecasters observed 3 natural windslab size 2 avalanches today on SE-NE aspects. One avalanche was triggered by cornice fall.

Snowpack Summary

Continuous moderate to strong west winds have formed wind effect and wind-slabs at alpine and tree-line elevations. The upper snowpack has a weak interface down 20-40 cm on the Jan 4 surface hoar/suncrust layer. The Nov 16 deep persistent layer is down 40-90 cm and continues to produce variable sudden test results. The mid and lower pack is weak in eastern regions and more supportive in western areas.

Weather Summary

Friday night: Alpine strong Westerly wind with up to 5 cm along the Continental Divide and West. Temperatures range from -5 to -10C

Saturday: Flurries continue and become less intense in the afternoon. 2-5 cm expected along the Divide and west. Winds ease in the afternoon to moderate. Alpine temperatures will be around -5C with freezing levels near 1400-1600 m

Sunday: A cold front descends through the region expect flurries (2-5 cm) with moderate-strong wind. Alpine high temperature near -5C.

More details can be found in the Mountain Weather Forecast

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • In times of uncertainty conservative terrain choices are our best defense.

Problems

Wind Slabs

An icon showing Wind Slabs

Continued moderate to strong W winds have formed wind effect and wind slabs in the alpine and treeline elevations. Ski hill forecasters found them to be more stubborn on Friday, but still observed some naturals and triggered them with explosives.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

The lower snowpack is comprised of weak facets and depth hoar with the upper snowpack forming a 40 to 90 cm thick slab above the weakness. Human triggering on this layer remains a concern.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 3.5

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