Avalanche Forecast

Archived

Jan 27th, 2023–Jan 28th, 2023

Alpine

Natural avalanches possible, human triggered probable.

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, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Regions

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

Forecast outflow winds will continue to build wind slabs at higher elevations, while buried weak layers continue to demand careful terrain selection.

Confidence

Moderate

Avalanche Summary

No new avalanche activity has been reported since the arrival of the cold, dry weather.

If you are out in the backcountry please consider filling out a Mountain Information Network report.

Snowpack Summary

In the alpine, recent strong winds and new snow have formed wind slabs in lee terrain features. While at lower elevations a widespread melt-freeze crust exists on the surface up to roughly 1900 m. This crust continues to gain strength and become supportive to travel with cold temperatures. At higher elevations, above 1900 m, surface snow has been redistributed by recent winds.

In the mid and lower snowpack, a number of buried weak layers remain a primary concern. These layers are most concerning in shallow, rocky areas at treeline and alpine elevations.

Weather Summary

Friday night

Mostly clear, no precipitation. Treeline temperatures -5 to -10 C. Moderate outflow winds in the alpine, while much stronger through valleys and inlets.

Saturday

Sunny, with no precipitation. Treeline temperatures -10 to -15 C. Light to moderate alpine winds, with strong to extreme outflow winds in valleys and inlets.

Sunday

Sunny, with no precipitation. Treeline temperatures 0 to -10 C. Light to moderate alpine winds, with strong to extreme outflow winds in valleys and inlets.

Monday

Sunny, with no precipitation. Treeline temperatures 0 to -5 C. Light northwest alpine winds.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be carefull around freshly wind loaded features.
If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.

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.