Avalanche Forecast

Issued: Apr 12th, 2024 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

Email

Conservative terrain travel is recommended. Recent large human-triggered avalanches have released on buried weak layers.

Summary

Confidence

Moderate

Avalanche Summary

Many natural and rider-triggered avalanches released on Thursday on the weak layers described in the Snowpack Summary (see photos below). These weak layers may take some time to strengthen, meaning they will likely remain active to human traffic for the foreseeable future.

Please consider sharing your observations to the Mountain Information Network.

Snowpack Summary

The alpine has received around 50 cm of snow over the past week. Wind from variable directions may have hardened the snow surface in wind-exposed terrain and formed deeper deposits in steep terrain near ridges.

Weak layers of surface hoar crystals and/or faceted grains may be found around 30 to 70 cm deep under the storm snow. This layer has produced recent avalanche activity and is unstable in snowpack tests.

Cornices are large and looming at this time of year.

Weather Summary

Friday Night

Cloudy with 1 to 3 cm of snow. 20 to 30 km/h southwest ridgetop wind. Treeline temperature -6 °C.

Saturday

Cloudy with 1 cm of snow. 20 km/h south ridgetop wind. Treeline temperature -5 °C.

Sunday

Mix of sun and cloud. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -4 °C.

Monday

Clear skies. 40 km/h north ridgetop wind. Treeline temperature -6 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be aware of the potential for larger than expected storm slabs due to the presence of buried surface hoar.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Storm Slabs

An icon showing Storm Slabs

Around 30 to 70 cm of storm snow over the week may rest on weak layers of surface hoar and/or faceted grains. These layers produced many large rider-triggered avalanches on Thursday. These layers may take some time to bond to the snowpack.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Likely

Expected Size

1.5 - 2.5

Valid until: Apr 13th, 2024 4:00PM