Avalanche Forecast

Archived

Feb 3rd, 2022–Feb 4th, 2022

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Regions

Cariboos.

A powerful storm is rapidly increasing avalanche danger. An avalanche cycle is expected over the coming days, especially where the snow is loading a buried weak layer.

Confidence

High - We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

THURSDAY NIGHT: Cloudy with snowfall, accumulation 5 to 15 cm, 20 to 40 km/h southwest wind, alpine temperature -8 C.

FRIDAY: Cloudy with snowfall, accumulation 5 to 15 cm, 40 to 60 km/h southwest wind, alpine temperature -7 C.

SATURDAY: Cloudy with snowfall, accumulation 5 to 10 cm, 40 to 60 km/h west wind, alpine temperature -6 C, freezing level rising to 1300 m.

SUNDAY: Mix of sun and cloud with no precipitation, 30 to 50 km/h southwest wind, alpine temperature -2 C, freezing level rising to 1800 m.

Avalanche Summary

A few small loose avalanches were observed out of steep terrain on Wednesday.

Natural and rider-triggered avalanche activity is expected to spike during Friday and into the weekend. Large avalanches are expected in areas where the buried surface hoar described in the Snowpack Summary exists. Avoidance of avalanche terrain is your best bet for having a safe day.

Snowpack Summary

Much of the region is forecast to get around 20 to 30 cm of snow over Friday, with locally higher amounts possible. The snow will rapidly build new slabs and create touchy avalanche conditions. In wind-exposed terrain, new wind slabs will rapidly form from strong wind. In sheltered terrain, the snow will form new storm slabs.

The snow will load a weak layer of surface hoar crystals found around 50 to 80 cm deep by the end of Friday. We've received indication that the surface hoar is likely most prominent in sheltered openings at and below treeline (e.g., open trees, cutblocks, burns) but could extend into wind-sheltered terrain in the alpine. On south aspects, a melt-freeze crust may exist instead of surface hoar.

The lower snowpack is generally strong and well-bonded.

Terrain and Travel

Travel in alpine terrain is not recommended.
Avoid all avalanche terrain during periods of heavy loading from new snow and wind.
Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
Watch for fresh storm slabs building throughout the day.
Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.

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.

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.