Avalanche forecast

Coquihalla

Feb 27 – 28, 2024Avalanche Canada
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Avalanche danger

Thu
Fri
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate

Highlights

Dangerous avalanche conditions exist at higher elevations where new snow struggles to bond to surfaces below

Human triggering potential persists as natural avalanche activity tapers off

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2.5

    25 to 50 cm of snow and moderate southwest winds have built reactive wind slabs at higher elevations. Give the slabs time to settle and bond before pushing into bigger terrain.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2.5

    A problematic combination of weak faceted snow and/or surface hoar over a crust remains a concern in isolated treeline terrain.

Confidence

Moderate

Avalanche Summary

No new avalanches had been reported in the region by 4 pm on Monday, however, operators who were in the field reported seeing signs of instability as they moved through the terrain, such as cracking and whumpffing. We expect users who head into the backcountry on Tuesday will see evidence of a natural storm slab avalanche cycle that occurred during the storm.

Snowpack Summary

Strong southwest winds have redistributed 25 to 50 cm of storm snow into wind slabs in lee terrain features at higher elevations. Recent snow overlies a variety of surfaces including surface hoar in sheltered terrain, and a crust on south-facing slopes. In exposed terrain at higher elevations, new snow covers old wind-affected surfaces.

A widespread crust is found down 60 to 100 cm, with weak, faceted snow immediately above it. This layer will need time to adjust to the new snow load, human-triggering remains a possibility.

Weather Summary

Monday Night

Partly cloudy with 0 to 5 cm of snow. 10 to 25 km/h northwest ridgetop wind. Treeline temperature -12 °C. Freezing level drops to valley bottom.

Tuesday

Cloudy with 0 to 2 cm of snow. 25 to 40 km/h southwest ridgetop wind. Treeline temperature -13 °C. Freezing levels remain at valley bottom.

Wednesday

Cloudy with snow switching to rain in the afternoon, accumulation 10 to 20 cm above the rain-snow line. Freezing level rises to 1500 m. 60 to 80 km/h southwest ridgetop wind. Treeline temperature -1 °C.

Thursday

Cloudy with 10 to 20 cm of snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -6 °C. Freezing level drops to 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.
  • Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
  • Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.

Regions covered