Avalanche Forecast

Archived

Feb 10th, 2025–Feb 11th, 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

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

Continually assess conditions as you move through terrain

Cold temperatures are softening the upper snowpack, avalanches are most likely where the snowpack feels “slabby”

Confidence

Moderate

Avalanche Summary

On Sunday, we received a report of a natural cornice failure which triggered a persistent slab avalanche, size 3, on a steep alpine feature. This avalanche is believed to have occurred on February 8.

On Saturday, a human-triggered, size 1, wind slab avalanche was reported on an open cross-loaded feature at treeline.

Numerous dry loose avalanches were reported. Naturals up to size 1, on steep solar aspects and human triggered, up to size 1.5, on steep polar aspects.

Snowpack Summary

Previous strong to extreme northeast outflow wind has scoured exposed terrain on all aspects at alpine and treeline. In sheltered terrain 10 to 40 cm of faceted snow overlies a surface hoar layer from late January.

Another layer of surface hoar was buried near the middle of January and can be found 30 to 60 cm deep.

A layer of facets and a crust from early December is buried 100 to 200 cm deep. This layer is generally not a concern in this region.

Weather Summary

Monday Night

Clear. 15 to 25 km/h north ridgetop wind. Treeline temperature -15 °C, potential for temperature inversion with a high of -10 °C in the alpine.

Tuesday

Sunny. 10 to 20 km/h north ridgetop wind. Treeline temperature -10 °C, potential for temperature inversion with a high of -5 °C in the alpine.

Wednesday

Sunny. 15 to 25 km/h northwest ridgetop wind. Treeline temperature -12 °C, potential for temperature inversion with a high of -7 °C in the alpine.

Thursday

A mix of sun and cloud. 15 to 25 km/h southeast ridgetop wind. Treeline temperature -13 °C.

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.
Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
Carefully evaluate steep lines for wind slabs.

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.