Avalanche forecast

South Rockies

Mar 9 – 10, 2023Avalanche Canada
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Avalanche danger

Sat
Sun
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low

Highlights

Avoid shallow rocky terrain where the snowpack transitions from thick to thin and triggering the deep persistent layer is more likely.

Avalanche problems

  • Wind Slabs

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

    Shifting winds have created wind slabs in lees of exposed features in the alpine and isolated features at treeline. Continually assess wind affect as you move through the terrain.

    Be aware that if triggered wind slab avalanches could step down to deeper layers.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    2–4

    The base of the snowpack remains very weak. Very large human triggered avalanches are possible at treeline and above. Avoid shallow and rocky areas, where the snowpack depth is highly variable. This is a very concerning avalanche problem and should stay in your mind when traveling in the backcountry.

Avalanche Summary

On Monday, a few natural, size three avalanches were observed in the region. A cornice triggered a wind slab avalanche on a steep rocky north-facing slope in the Selkirks. In the Rockies, a deep persistent slab avalanche was triggered by a cornice or solar input in extreme, rocky terrain. See the MIN for a photo.

Confidence

Moderate

Snowpack Summary

40-50 cm of storm snow from earlier in the week sits over wind affected surfaces in sheltered locations. Wind slabs may be found on all aspects due to variable winds in the past few days. A melt-freeze crust covers the surface of steep solar slopes.

The mid-snowpack is generally well settled. The lower snowpack is made up of a widespread layer of large, weak basal facets and depth hoar in some areas. this weakness has been responsible for a number of recent very large, destructive avalanches and will continue to be a concern.

Weather Summary

Wednesday Night

Partly cloudy. Easterly ridgetop winds 15-25 km/h. Treeline temperatures, low of -15.

Thursday

A mix of sun and cloud with isolated flurries, trace accumulation. Southerly winds 15-25 km/h. Treeline temperatures, high of -10.

Friday

Cloudy with scattered flurries, 3-6 cm accumulation. Easterly ridgetop winds 15-25 km/h. Treeline temperatures, high of -10.

Overnight flurries continue 2-3 cm accumulation. Winds switch to the southwest 20 km/h.

Saturday

Partly cloudy with isolated flurries, trace accumulation. Southwest ridgetop winds 20 km/h. Treeline temperatures, high of -10.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid areas with a thin or variable snowpack.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.

Regions covered