Avalanche forecast

South Coast

Mar 17 – 18, 2023Avalanche Canada
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Avalanche danger

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

Rising freezing levels and the sun can quickly destabilize the snowpack. Avoid sun-exposed slopes and overhead hazards like cornices during the heat of the day.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    1–1.5

    Pockets of stiff wind slab may be reactive to human triggering on lee slopes at upper elevations.

  • Cornices

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1.5–2.5

    Large looming cornices exist along ridgelines. Cornices become weak with daytime warming and sun exposure. Give cornices a wide berth while traveling ridgelines and avoid slopes below them.

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Strong solar radiation and rising freezing levels may weaken the surface snow creating wet loose avalanches on sunny slopes at higher elevations to all aspects below 1500 m.

Confidence

Moderate

Avalanche Summary

On Thursday, wet-loose avalanches to size 1.5 were reported from solar slopes and steep, rocky terrain.

On Wednesday, pinwheeling was seen on solar aspects and small dry loose sluffing seen on shaded aspects.

On Tuesday, natural and skier-triggered dry loose avalanches up to size 1 were reported from the North Shore mountains.

On Monday, natural dry loose avalanches were reported from steep terrain features and explosive control initiated several storm slabs up to size 1. The storm slabs were 5 to 20 cm thick with very limited propagation and entrainment.

Natural and human-triggered avalanche activity will likely occur throughout the weekend with rising freezing levels and solar radiation.

Snowpack Summary

Daytime warming and solar radiation will promote moist snow surfaces, destabilizing the upper snowpack on all aspects up to 1300 m. Above this only steep solar slopes will be affected while northerly aspects should hold the dryer wintery snow longer. Southerly winds have also created wind slabs in exposed terrain at higher elevations.The recent 40 cm of storm snow is reportedly settling and bonding to the old buried crusts.

In general, the mid and lower snowpack is well-settled and bonded.

Weather Summary

Friday night

Scattered clouds and starry breaks. Treeline low temperatures -2. South wind 20-30 km/hr. Freezing level 1400 m.

Saturday

Mix of sun and cloud. South wind 15-20 km/hr. Treeline high temperature +7. Freezing level 1800 m.

Sunday

Showers start near the end of the day, 10-20 mm overnight. Southeast wind increasing to 30-40 km/hr. Treeline high temperature +4, freezing level dropping to 1500 m.

Monday

Rain transitioning to snow at higher elevations, 10 mm. South wind gusting to 30 km/hr. Treeline temperature high +2, freezing level 1000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.
  • Minimize exposure to sun-exposed slopes when the solar radiation is strong.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Regions covered