Avalanche Forecast

Issued: Mar 17th, 2024 4:00PM

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

Avalanche Canada ejones, Avalanche Canada

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Southwest winds have formed deposits of reactive wind slab.

Seek out sheltered terrain.

Summary

Confidence

Moderate

Avalanche Summary

Many size 2 explosive-triggered avalanches were reported in the Pass on Friday. Some small loose wet slides occurred on sunny slopes during the day on Saturday.

Several natural wind slab avalanches, up to size 2, were reported to have failed above the highway on Thursday night.

Otherwise, field observations have been limited. If you head into the backcountry, please submit your observations to the Mountain Information Network.

Snowpack Summary

Warm temperatures over the weekend may have created a surface crust up to 1500 m.

Storm totals reached 50 cm by Sunday. Strong south winds have redistributed this snow into deep, reactive wind slabs in leeward terrain. This snow overlies firm surfaces and is not expected to bond well. In isolated areas, buried surface hoar may be found 60 to 75 cm deep. The mid-pack is generally strong and bridges the weak crystals at the base of the snowpack.

Weather Summary

Sunday Night

Cloudy with 2 cm of new snow. 40 to 50 km/h southwest ridgetop wind. Treeline temperatures around -3 °C. Freezing level drops to 500 m.

Monday

Cloudy with trace snow flurries in the morning. 30 to 40 km/h southwest ridgetop wind. Treeline temperatures around -2°C. Freezing level 900 m.

Tuesday

Cloudy with a trace of snow flurries. 30 km/h north ridgetop wind. Treeline temperatures around -1 °C. Freezing level 1000 m.

Wednesday

Cloudy with a trace of snow flurries. 40 km/h north ridgetop wind. Treeline temperatures around -3 °C. Freezing level 800 m.

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.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
  • Choose low-angled, sheltered terrain where new snow hasn't been wind-affected.

Problems

Wind Slabs

An icon showing Wind Slabs

Southwest winds have formed reactive slabs on leeward terrain. These slabs will likely fail on firm, old surfaces.

Watch for corniced ridges, cross-loaded features, and convex rollovers.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Valid until: Mar 18th, 2024 4:00PM