Avalanche Forecast

Issued: Apr 20th, 2024 4:00PM

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

Avalanche Canada jsmith, Avalanche Canada

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Large persistent slab avalanches may remain possible to human trigger at treeline and above.

Avoid steep or convex slopes where triggering slabs is more likely.

Summary

Confidence

Moderate

Avalanche Summary

A few naturally triggered wind slab avalanches up to size 2 were reported on a variety of aspects in the alpine on Friday.

Field observations are currently very limited in this region. Please consider sharing your observations to the Mountain Information Network.

Snowpack Summary

A hard melt-freeze crust exists on the snow surface on sun-exposed slopes to the mountain tops. The crust will transition to wet snow with daytime warming and generally re-freeze at night.

Dry snow may still be found on true north aspects at upper elevations.

In isolated locations, a weak layer of facets and/or surface hoar is down 50 to 100 cm. It is most likely to be in terrain sheltered from the wind at treeline and above.

Weather Summary

Saturday night

Increasing cloudiness. 10 to 20 km/h west ridgetop wind. Treeline temperature -1 °C. Freezing level 1300 m.

Sunday

Mostly cloudy. 20 to 30 km/h west ridgetop wind. Treeline temperature 0 °C. Freezing level 1400 m.

Monday

Mix of sun and cloud. 10 to 20 km/h southwest ridgetop wind. Treeline temperature -1 °C. Freezing level 1300 m.

Tuesday

Cloudy with flurries, 5 to 10 cm snow. 20 to 30 km/h southeast ridgetop wind. Treeline temperature -1 °C. Freezing level 1300 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be aware of the potential for surprisingly large avalanches due to deeply buried weak layers.
  • Avoid steep convex slopes.
  • Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Persistent Slabs

An icon showing Persistent Slabs

In isolated locations, a weak layer of facets and/or surface hoar is down 50 to 100 cm. It is most likely to be in terrain sheltered from the wind at treeline and above.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1.5 - 2.5

Valid until: Apr 21st, 2024 4:00PM