Avalanche Forecast

Issued: Mar 12th, 2024 4:00PM

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

Avalanche Canada jleblanc, Avalanche Canada

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Surprising skier-triggered avalanches, including some step-down, are evidence of reactive persistent slabs. Keep choosing low-consequence slopes with no overhead hazard.

Summary

Confidence

Moderate

Avalanche Summary

Large and very large slabs and accidentally triggered avalanches continue to occur across the region. On Monday, numerous surprising avalanches were skier-triggered at treeline, including a step-down. Some have been triggered from low-angle terrain onto adjacent slopes. We expect the potential for riders to trigger avalanches will remain elevated over the following days.

For more information, click on the photos below.

Snowpack Summary

Recent storm snow, now totalizing 40 to 80 cm, has formed reactive slabs across the region. Several persistent weak layers are now buried between 80 and 160 cm deep, including hard crusts with overlying weak facets and surface hoar. These weak layers have been responsible for continued avalanche activities over the last week.

At lower elevations, the upper snowpack may be moist or crusty.

Weather Summary

Tuesday Night

Cloudy with 2 of new snow expected. 30 to 40 km/h south ridgetop wind. Treeline temperatures around 0 °C. Freezing level returning to valley bottom.

Wednesday

Cloudy with 3 to 5 cm of new snow expected. 50 to 70 km/h southwest ridgetop wind. Treeline temperatures around 0 °C. Freezing level rising to 1200 m.

Thursday

Cloudy with 10-20 cm of new snow expected. 60 to 80 km/h southwest ridgetop wind. Treeline temperatures around +3 °C. Freezing level rising to 1500 m.

Friday

Cloudy with no precipitation. 40 to 60 km/h southwest ridgetop wind. Treeline temperatures around +5 °C. Freezing level rising to 2500 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Remote triggering is a big concern, be aware of the potential for wide propagations and large, destructive avalanches at all elevations.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
  • Avoid open slopes and convex rolls at and below treeline where weak layers may be preserved.

Problems

Persistent Slabs

An icon showing Persistent Slabs

Persistent weak layers including crust/facet combos and buried surface hoar continue producing surprising avalanches. Be aware of the potential for wide propagation, especially at treeline.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 3

Storm Slabs

An icon showing Storm Slabs

Ongoing snowfalls and winds will continue to create reactive storm slabs. The largest and most reactive are expected to be on northerly aspects. Storm slabs in motion may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

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