Avalanche Forecast

Archived

Dec 24th, 2023–Dec 25th, 2023

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

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

Avalanche hazard will increase throughout the day as storm snow accumulates. Dail back your terrain choices if you are finding +30 cm of storm snow.

Happy holidays, enjoy the fresh snow!

Confidence

Moderate

Avalanche Summary

On Saturday, a size 1, skier accidental storm slab avalanche was reported near Terrace. This was on a northwesterly feature at treeline.

Operators in the region reported evidence of a natural storm slab avalanche cycle from the past 48 hours. Avalanches averaged size 1.5 - 2.

If you head into the backcountry please consider submitting your observations to the Mountain Information Network.

Snowpack Summary

Storm snow accumulates throughout the day over wind affected surfaces in exposed areas and 50 to 70 cm of settling snow in sheltered areas.

Two buried layers of surface hoar are widespread in the mid snowpack, buried 50-100 cm, and 90-130 cm deep.

The remaining mid and lower snowpack contains several crusts from early in the season that are generally well-bonded to the surrounding snowpack. Snow depths are highly variable depending on elevation, and decrease rapidly below treeline.

Weather Summary

Sunday Night

Cloudy with isolated flurries, 1-3 cm of snow. Southerly winds ease slightly, 40-60 km/h. Freezing levels remain around 700 m, and treeline temperatures around -5 °C.

Monday

Cloudy with flurries, widespread 10-20 cm for the region, up to 40 cm in the Kitimat area. Southerly winds 60-100 km/h. Freezing levels rise towards 1500 m on the immediate coast, 500m in the Terrace area. Treeline temperatures approach -2°C.

Overnight flurries continue bringing another 10 to 20 cm of snow expected.

Tuesday

Cloudy with flurries, 5- 10 cm of snow. Southwest winds, 40-70 km/h. Freezing levels around 1000 m, treeline temperatures around -3°C.

Wednesday

Mainly cloudy with flurries, 5- 10 cm of snow. Southeast winds, 60-80 km/h. Freezing levels around 800 m, treeline temperatures around -3°C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Watch for signs of slab formation throughout the day.
Be carefull around freshly wind loaded features.
Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.

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.