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, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Regions

Kitimat, Nass, Rupert, Seven Sisters, Shames, Howson.

Riders may still trigger wind slabs.

Keep in mind, buried weak layers could result in large avalanches.

Confidence

Moderate

Avalanche Summary

On Saturday, there was one large (size 2) natural wind slab in the alpine from a southeast aspect in the sun. As well as several wet loose avalanches on Sunday size 1-2).

On Friday, north of the Sleeping Beauty Provincial Park. Ski cutting produced a few small (size 1) wind slab avalanches with one large (size 2) remotely triggered persistent slab avalanche.

Snowpack Summary

Up to 35 cm of new snow is possible above 1500 m and has buried a melt freeze crust. At low elevations, It's likely a crust will form Monday night as the sky clears and temperatures drop.

Three persistent weak layers remain notable in the snowpack.

Surface hoar that formed in mid-March can be found 50 to 100 cm below the snow surface.
A layer of surface hoar that formed in early March can be found at a depth of 100 to 150 cm.
A layer of facets, surface hoar, and/or a crust from mid-February is buried 100 to 200 cm deep.

At elevations below treeline, the snow pack is rain saturated and isothermal.

Weather Summary

Monday Night

Partly cloudy with 1 or 2 cm of snow. 30 to 50 km/h west ridgetop wind. Treeline temperature -5 °C. Freezing level 900 m.

Tuesday

Mostly cloudy. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -4 °C. Freezing level 900 m.

Wednesday

Mostly sunny. 15 km/h north ridgetop wind. Treeline temperature -1°C. Freezing level 1700 m.

Thursday

Mostly sunny. 10 km/h variable direction ridgetop wind. Treeline temperature +10 °C. Freezing level 3200 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be careful as you transition into wind-affected terrain.
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.

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.

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.

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.