Avalanche forecast

South Okanagan

Dec 3 – 4, 2022Avalanche Canada
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Avalanche danger

Mon
Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Start simple! We have a lot of uncertainty: very few field reports for this forecast region, and a reactive layer of surface hoar primed for human triggering in the forecast regions to the east.

Choose conservative terrain and investigate the bond of the new snow.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Southerly winds have impacted snow at upper elevations, incoming northwest wind may reverse-load features. There's a lot of loose snow out there, expect fresh slabs to form where the wind picks up.

    Reports suggest the recent 15-30 cm is poorly bonded to the interface below (a layer of surface hoar). Keep an eye on the wind, slabs may quickly form wherever the wind encourages the fresh snow to bond; and with a weak layer of surface hoar below, reactive slabs may be more widespread, extend into treeline elevations, and be more reactive than expected in sheltered areas.

Confidence

Low

Avalanche Summary

No new avalanches have been observed or reported in this region. However, note that we have had no field observations in for this forecast region this winter.

Potential for skier-trigger avalanches are likely to be found on terrain features that harbor additional snow such as just below ridgetops and on steep wind-loaded slopes.

Snowpack Summary

15-30 cm fresh snow blanketed the region over the last few days. Southwest winds have impacted loose snow at upper elevations. In the Columbia and Kootenay-Boundary Forecast regions, a layer of surface hoar down 30-50 cm (below the new snow) has been quite reactive with extensive reports of whumpfing and cracking. This layer is likely found throughout our forecast region, but we need more field observations to determine its extent and sensitivity.

Snowpack depths exceed 100 cm at upper elevations. In these deeper areas around 65 cm of snow overlies a weak layer from mid-November that consists of sugary faceted grains, weak surface hoar crystals in sheltered terrain features, and a hard crust on steep sun-exposed slopes.

Weather Summary

Friday night

Cloudy with light flurries, trace to 5 cm overnight. Increasing southwest wind 10-20 km/hr. Treeline temperature low -15 °C.

Saturday

Partly cloudy with sunny breaks in the afternoon. Southwest wind 10-20 km/hr decreasing through the day. Treeline high temperature -6 °C.

Sunday

Clear, cold, and calm. Light northeast wind, treeline high temperatures -10 °C.

Monday

Cold with incoming clouds and wind. Southwest wind increasing to strong. Treeline temperatures -12 C, wind chill lower.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Pay attention to the wind, once it starts to blow fresh sensitive wind slabs are likely to form.
  • Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
  • Closely monitor how the new snow is bonding to the old surface.

Regions covered