Avalanche forecast

Northwest Inland

Mar 12 – 13, 2021Avalanche Canada
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Avalanche danger

Sun
Mon
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
3 · Considerable

Highlights

Up to 35 cm new snow by the end of the day on Friday with strong southwest wind will form reactive storm slabs and wind slabs. The avalanche danger will increase throughout the day. A good day to make conservative terrain choices! 

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely - Very Likely
    Size
    1–2

    Up to 15 cm overnight and another 10 to 20 cm during the day on Friday will form reactive storm slabs. Strong southwest wind will redistribute the new snow and develop wind slabs in lee terrain features in the alpine and at treeline.

    The wind will contribute to cornice growth.

Confidence

High - We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

THURSDAY NIGHT: Cloudy, up to 15 cm new snow, 60 km/h southwest wind, alpine low -8 C. 

FRIDAY: Cloudy, 10 to 20 cm new snow, 50 km/h southwest wind, alpine high -5 C.

SATURDAY: Mostly cloudy, 10 to 20 cm new snow, 50 km/h south wind, alpine high +2 C, freezing level rising to 1600 m.

SUNDAY: Mostly cloudy, 10 to 15 cm new snow, 30 km/h south wind, alpine high -4 C, freezing level 1100 m.

Avalanche Summary

No new avalanches were observed on Thursday at the time of writing. Looking ahead, newly formed storm slabs and wind slabs will be the primary concern on Friday. 

Snowpack Summary

The storm will bring up to 35 cm new snow with strong southwest wind on Friday. The new snow may overly widespread wind affect at alpine elevations, feathery surface hoar on northerly aspects and in sheltered terrain features around treeline, or a melt-freeze crust on southerly aspects and below treeline.

There are presently no widespread deeper concerns. However, faceted snow at the base of the snowpack exists in much of the region and always has the potential of being triggered in shallow, rocky slopes.

Terrain and Travel

  • Watch for fresh storm slabs building throughout the day.
  • 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.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Regions covered