Avalanche Forecast

Archived

Apr 14th, 2025–Apr 15th, 2025

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.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Regions

Northwest Coastal, Northwest Inland, Boundary, Stewart, Kispiox, Ningunsaw, Ningunsaw, Ningunsaw.

Large persistent slabs continue to occur sporadically.

Sticking to conservative terrain is the easiest way to stay safe.

Confidence

Moderate

Avalanche Summary

On Sunday, there were several large cornice and storm slabs (size 1.5-2) both natural and explosive triggered on north and west aspects in the alpine.

Last Friday, a failing cornice triggered a size 3 avalanche on an eastern slope in the alpine. This avalanche is believed to have occurred on the March 5th surface hoar layer.

Where a thick, supportive surface crust is found, we expect that triggering avalanches on buried weak layers is unlikely.

Snowpack Summary

Up to 40 cm of recent snow has fallen over various recent crusts which are found up to 1800 m, higher on sunny slopes.

Three layers of note, currently exist in the mid-snowpack:

A layer of surface hoar and a crust that formed in mid-March is 50 to 80 cm below the snow surface.
Another layer of surface hoar that formed in early March buried 70 to 120 cm.
A layer of facets, surface hoar, and/or a crust from mid-February is buried 120 to 200 cm deep.

The remainder of the snowpack is well consolidated.

Weather Summary

Monday Night

Mostly cloudy with 0 to 2 cm of snow. 20 to 40 km/h southwest ridgetop wind. Treeline temperature -6 °C.

Tuesday

Mostly cloudy with 0 to 1 cm of snow. 20 to 30 km/h west ridgetop wind. Treeline temperature -5 °C.

Wednesday

A mix of sun and cloud. 10 km/h variable direction ridgetop wind. Treeline temperature -3°C. Freezing level 1400 m.

Thursday

A mix of sun and cloud. 10 km/h southwest ridgetop wind. Treeline temperature 0°C. Freezing level 3000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
Be aware of the potential for large, destructive avalanches due to deeply buried weak layers.
Cornice failures could trigger large and destructive avalanches.
Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

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.