Avalanche Forecast

Archived

Jan 31st, 2024–Feb 1st, 2024

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

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

South Coast Inland, Birkenhead, Duffey, South Chilcotin, Stein, Taseko.

New wind slabs are one reason to tread carefully on Thursday, the extensive recent avalanche cycle is another. Avoid rushing into (or under) large terrain until the snowpack has stabilized.

Confidence

Moderate

Avalanche Summary

A widespread avalanche cycle took place in the region through the early week, with numerous wet slab and wet loose avalanches to size 4 (very large) seen in a wide range of terrain. One report from Tuesday featured a size 4 with a crown fracture over 3 km long!

Looking ahead, light new snow should generate surface instabilities as cooling temperatures reduce the odds of deep avalanches. Given the scale of recent activity, there's no rush to jump back into large terrain.

Snowpack Summary

Alpine elevations ought to collect 10-25 cm of new snow on a surface crust by end of day Thursday. Otherwise, light rain will keep the upper snowpack at treeline and below largely saturated with water.

The mid and lower snowpack consists of variable layers of crusts and faceted snow.

Overall the snowpack remains unusually shallow and continues to melt at lower elevations.

Weather Summary

Wednesday night

Cloudy with light rain or wet snow, possible 5-10 cm accumulating in the hight alpine. South alpine winds 20 to 40 km/h, freezing level around 2000 m.

Thursday

Cloudy with 5-15 cm of new snow in the alpine, rain below 1700 m. South alpine winds 10 to 20 km/h. Treeline temperature 0°C with freezing level around 1800 m.

Friday

Mostly cloudy with scattered flurries bringing less than 5 cm of new snow. Southwest alpine winds 10 to 20 km/h. Treeline temperature 0°C with freezing level around 1700 m.

Saturday

A mix of sun and cloud with isolated flurries. Alpine winds shifting northeast, 5-10 km/h. Treeline temperature -2°C with freezing level around 1400 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Keep in mind that wet avalanches can be destructive due to their high density.
Avoid areas with overhead hazard.

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.

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.

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.