Avalanche Forecast

Issued: Jan 13th, 2024 4:00PM

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

Avalanche Canada wlewis, Avalanche Canada

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Watch for active wind transport building fresh and reactive slabs on south facing slopes.

Sheltered areas should hold great riding conditions, seek them out and be aware of overhead hazard.

Summary

Confidence

Moderate

Avalanche Summary

Naturally triggered wind slabs were reported on Friday, in wind affected features at higher elevations. We expect reactivity to continue.

Activity on the buried weak layers was last reported on Wednesday, with a size 2.5 on a reloaded (weaker) bed surface in a northwest facing slope in the alpine. Last Saturday, a very large avalanche was reported on Joffre shoulder. Persistent avalanches are still possible in shallow snowpack areas, or from step down avalanches.

Snowpack Summary

Wind slab exists on south facing slopes at treeline and above, from northerly winds. Slabs may overly wind affected surfaces or surface hoar in sheltered areas.

A crust is found at treeline and below, 40-80 cm down. In some areas, a layer of surface hoar exists above the crust.

Another weak layer of facets or surface hoar overlying a crust is found at the base of the snowpack down 80 to 120 cm. This is the suspected failure plane for large avalanches in the region that occurred on January 6th and 10th. While the reactivity appears to be decreasing, triggering is most likely at high elevations where the snowpack is shallow.

Snowpack depths are 100 to 140 cm at treeline and decrease rapidly below.

Weather Summary

Saturday Night

Clear skies with northerly winds increasing 15-50 km/h. Treeline temperatures rise to -18 °C.

Sunday

Sunny with northerly winds 20-50 km/h. Treeline temperatures around -17 °C.

Monday

Sunny with northerly winds easing 10-20 km/h. Treeline temperatures rise to -13 °C.

Tuesday

Sunny with southwest winds winds strengthening, 15-50 km/h. Treeline temperatures rise to -11 °C.

With unusually cold temperatures forecast for this weekend, check out the most recent Forecaster Blog for tips on backcountry preparedness.

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.
  • Expect slab conditions to change drastically as you move into wind exposed terrain.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs may be found near ridgelines or lower on the slope than usual. Watch for crossloading in unusual features like mid slope gullies and rollovers.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 14th, 2024 4:00PM