Avalanche Forecast

Archived

Mar 24th, 2024–Mar 25th, 2024

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

Northwest Coastal, Boundary, Kitimat, Nass, Rupert, Seven Sisters, Shames, Stewart, Howson, Ningunsaw, Ningunsaw, Ningunsaw.

While natural avalanche activity has tapered off in many areas, human triggering remains a concern with buried weak layers.

Confidence

Moderate

Avalanche Summary

On Saturday, three very large (size 3) persistent slab avalanches were observed in the very north of the region. They occurred on south-facing alpine slopes and were likely triggered by daytime warming.

Loose wet avalanches were also observed from steep sunny slopes, ranging from small to large (size 1 to 2).

Snowpack Summary

A thick widespread crust exists on the surface in most areas. The surface crust may soften throughout the day at lower elevations and on steep sunny slopes.

At lower elevations, the snow below the crust is likely moist or wet to the ground, or the snowpack may be isothermal.Dry powder snow still exists in northern parts of the region on north-facing alpine slopes.

A weak layer of surface hoar is developing in sheltered terrain at treeline and above.

Various weak layers, including crusts, facets, and/or surface hoar exist approximately 40 to 90 cm deep. An additional crust and facet layer may be found 150+ cm below the surface.

Weather Summary

Sunday Night

Mostly clear. 20 to 30 km/h southwest ridgetop wind. Treeline temperature drops to around -3 °C. Freezing level dropping to 500 m near Terrace and 300m near Stewart.

Monday

Partly cloudy with 1 to 2 cm of new snow. 20 km/h northwest ridgetop wind. Treeline temperature rising to 0 °C. Freezing level rising to 1300 m.

Tuesday

Mostly cloudy with 1 to 4 cm of new snow. 20 km/h west ridgetop wind. Treeline temperature 0 °C. Freezing level rising to 1300 m.

Wednesday

Partly cloudy with a trace of new snow possible. 40 to 60 km/h southeast ridgetop wind. Treeline temperature -1°C. Freezing level rising to 1400 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Keep in mind that human triggering potential persists as natural avalanching tapers off.

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.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.