Avalanche Forecast

Archived

Apr 18th, 2025–Apr 19th, 2025

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

Microwave-Sinclair, North Bulkley, South Bulkley, South Bulkley, South Bulkley, Telkwa.

Lingering concern remains for buried weak layers in the snowpack. A cautious approach is recommended during times of uncertainty.

Confidence

Low

Avalanche Summary

On Thursday, a skier triggered a size 2 wind slab on a NE aspect at 2350 m, which was 10-20 cm thick. Natural wet loose avalanches up to size 2.5 and natural cornice releases were also observed.

On Wednesday, a natural cornice fall triggered a size 2.5 wind slab in the west of the region. This occurred on a NW aspect at 2300 m, and the slab was 100 cm thick.

Snowpack Summary

A widespread surface crust is expected to have formed following Thursday's warming event.

Two layers currently exist in the mid-snowpack and remain an isolated concern:

A layer of surface hoar that formed in early March can be found at a depth of 40 to 70 cm.
A layer of facets, surface hoar, and/or a crust from mid-February is buried 60 to 120 cm deep.

Weather Summary

Friday Night

Cloudy with snowfall up to 3 cm. 30 to 40 km/h west ridgetop wind. Treeline temperature -5 °C. Freezing level valley bottom.

Saturday

Cloudy with snowfall up to 6 cm. 20-30 km/h northwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1100 m.

Sunday

A mix of sun and cloud with lingering flurries in the morning. 10 to 20 km/h northwest ridgetop wind. Treeline temperature 0 °C. Freezing level 1400 m.

Monday

Mostly sunny. 10 to 20 km/h northwest ridgetop wind. Treeline temperature +1 °C. Freezing level 1600 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be aware of the potential for large avalanches due to buried weak layers.
Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.

Problems

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.