Avalanche forecast

South Columbia

Mar 30 – 31, 2022Avalanche Canada
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Avalanche danger

Fri
Sat
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
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Highlights

Conditions may change quickly with rain or strong solar input. Be ready to scale back your exposure to avalanche terrain if the surface crust breaks down.

Cautious route-finding will be important at upper elevations as wind slabs may be reactive to human triggering.

Avalanche problems

  • Wind Slabs

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

    Wind slabs may exist in steep, lee terrain features in the alpine and exposed treeline. These slabs will be most reactive where they overlie a slick crust.

  • Cornices

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–3

    Springtime cornices are large and unpredictable. Give them a wide berth when travelling at ridge crest and avoid overhead exposure, especially when the air temperature is warm or solar radiation is strong.

  • Wet Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    1–3

    Avoid avalanche terrain if the snowpack becomes wet and unsupportive to your weight. At lower elevations, a poor overnight crust recovery followed by above freezing temperatures and rain may cause wet slab and wet loose avalanches to continue on all aspects. 

     If the sun comes out on Thursday, wet loose activity can be expected on steep solar aspects at all elevations. 

Confidence

Low - Uncertainty is due to how quickly the snowpack will recover and gain strength. Uncertainty is due to the timing or intensity of solar radiation and its effect on the snowpack.

Weather Forecast

WEDNESDAY NIGHT: Cloudy with flurries in the north of the north, up to 5 cm of accumulation. Partially cloudy in the south. Freezing level dropping to around 500 m. 15-35 km/h northwesterly winds.

THURSDAY: Partially cloudy, isolated flurries. Freezing level rising to 1300 m. 10-30 km/h northwesterly winds.

FRIDAY: Mainly cloudy, flurries in the afternoon. Freezing level rising to 1500 m/ 10-25 km/h southwest winds.

SATURDAY: Partially cloudy with isolated flurries. Freezing level rising to 1600 m. 10-20 km/h southwest winds.

Avalanche Summary

On Tuesday in the north of the region, several size 1-2 natural wind slabs were observed in the alpine. Throughout the region, a widespread wet loose/wet slab avalanche cycle occurred at all elevations up to size 3. The most reactivity was noted on solar aspects.  

A widespread wet loose/slab natural avalanche cycle up to size 3 occurred on Monday on all aspects and elevations.

The last persistent slab avalanches observed in the region were during the warm-up on March 23rd and 24th.This layer is expected to become dormant after being tested by significant warming followed by cooling temperatures. 

Snowpack Summary

5 to 15 cm of new snow overlies 10-20 cm of denser snow above 2000 m. Southwest winds may form small wind slabs in lee terrain features in the alpine and treeline. A crust or moist snow can be found below the new snow on all aspects below 2500m. Below the crust, the top 10-30 cm of the snowpack is moist.

Several other layers exist in the upper snowpack, that have shown no recent reactivity.

Terrain and Travel

  • As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.
  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
  • The more the snow feels like a slurpy, the more likely loose wet avalanches will become.
  • Carefully evaluate steep lines for wind slabs.
  • Wind slabs may be poorly bonded to the underlying crust.
  • Cornices become weak with daytime heating or solar exposure.

Regions covered