Avalanche Forecast

Issued: Apr 4th, 2021 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

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Wind slabs may linger up high. Use caution during the heat of the day as cornices and the recent snow warm up.

Summary

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

SUNDAY NIGHT: Clear skies, 20 km/h northwest wind, alpine temperature -6 C.

MONDAY: Clear skies, 10 km/h west wind, alpine temperature 0 C, freezing level rising to 2000 m.

TUESDAY: Mix of sun and clouds, 10 km/h southwest wind, alpine temperature -2 C, freezing level 1800 m.

WEDNESDAY: Cloudy with snowfall, accumulation 5 to 10 cm, 20 km/h southwest wind, alpine temperature -8 C.

Avalanche Summary

A natural avalanche cycle was observed in the region on Saturday during the storm. Looking forward, wind slabs could still be triggered by riders at high elevations and a warming trend has the potential to increase avalanche activity as the snowpack weakens.

Snowpack Summary

Saturday's storm brought 15 to 25 cm around the Hurley and Duffey, 15 cm around Coquihalla, and 5 cm around Manning, all above around 1600 m. The snow fell with strong southwest wind, forming wind slabs in lee terrain features at high elevations. The snow overlies a hard melt-freeze crust everywhere except for north aspects above around 1600 m, where it fell onto previously dry snow. The snow surface may have already melted and frozen into a crust on sun-exposed aspects. Warm air and sunny skies will likely moisten the snow on Monday, particularly on sun-exposed slopes.

Cornices are large and looming along ridgelines. Their release is unpredictable, requiring a large berth if you're travelling above or below them.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Closely monitor how the new snow is bonding to the crust.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • Avoid sun exposed slopes, especially if snow surface is moist or wet.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs could still be triggered by riders in steep, lee terrain features at high elevations. Carefully evaluate for wind slabs prior to committing to consequential avalanche terrain.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Cornices

An icon showing Cornices

Cornices are large and looming along many ridgelines, and have likely grown with the recent snow and wind. They become increasingly weak when the sun comes out and freezing levels rise. They require a large berth when travelling above and below them. 

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

2 - 3

Loose Wet

An icon showing Loose Wet

The recent snow may moisten and form wet loose avalanches during the heat of the day, especially on sun-exposed slopes. The most likely areas to get into trouble would be on steep slopes above terrain traps. 

Aspects: South East, South, South West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 5th, 2021 4:00PM