Avalanche Forecast

Issued: Apr 16th, 2024 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

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Human triggering of a buried weak layer remains possible. The likelihood of warming-related avalanches will increase during the heat of the day.

Summary

Confidence

Moderate

Avalanche Summary

No recent avalanches were observed in the region. The most recent persistent slab activity occurred last Thursday. Although the likelihood is decreasing, it remains possible for humans to trigger this buried weak layer.

Snowpack Summary

Dry, settled snow is found on shaded aspects in the alpine. A hard melt-freeze crust is found on the snow surface on sun-exposed slopes to the mountain tops and on all aspects below treeline. The crust will transition to wet snow with daytime warming and re-freeze at night.

50 to 100 cm of snow overlies a hard melt-freeze crust from early April. The overlying snow is slow to bond to the crust where pockets of weak surface hoar or faceted grains rest on the crust, which is most likely on northerly aspects at treeline and alpine elevations.

Weather Summary

Tuesday Night

Clear skies. 10 km/h east ridgetop wind. Treeline temperature -4 °C.

Wednesday

Clear skies. 10 to 20 km/h east ridgetop wind. Treeline temperature -1 °C. Freezing level rising to 1200 m.

Thursday

Clear skies. 10 to 20 km/h east ridgetop wind. Treeline temperature 0 °C. Freezing level rising to 1500 m.

Friday

Clear skies. 20 to 30 km/h east ridgetop wind. Treeline temperature 0 °C. Freezing level rising to 1500 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.
  • 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.
  • Back off slopes as the surface becomes moist or wet with rising temperatures.

Problems

Loose Wet

An icon showing Loose Wet

Wet loose avalanches are likely in steep terrain during the heat of the day. Cornices are also weakening and could release. These avalanches could step down to deeper layers, forming large avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A weak layer of facets and/or surface hoar is buried around 50 to 100 cm deep. The layer is most prominent on terrain features sheltered from the wind.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Valid until: Apr 17th, 2024 4:00PM