Avalanche Forecast

Archived

Feb 16th, 2024–Feb 17th, 2024

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

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

Many wind slabs were human triggered and even remotely triggered in recent days as slabs formed over a dangerous mix of weak grains and crust. Daytime warming could increase this reactivity.

Confidence

High

Avalanche Summary

Wind slab reactivity continues to be the focus in recent reports. In the Hurley area on Thursday, a very large (size 3) natural wind slab release was observed on a steep north aspect in the alpine. This added to numerous other skier and remote-triggered wind slabs in the region, mainly to size 1.5.

Similarly reactive conditions have been observed on a variety of aspects in the alpine and upper treeline in recent days and are expected to persist through the forecast period.

Snowpack Summary

Wind and sun have created variable surface conditions, with northeast wind heavily impacting open terrain.

15 to 30 cm of snow sits above a widespread crust. Many areas have reported a weak surface hoar layer above this crust, which could be problematic in areas where wind has formed a slab above the layer.

Snowpack depths decrease rapidly below treeline.

Weather Summary

Friday night

Clear. Southeast alpine wind 15 - 20km/h

Saturday

Increasing high cloud in the afternoon. South alpine winds 5 - 10 km/h. Treeline temperature -2 °C.

Sunday

Cloudy with isolated flurries. Southwest alpine wind 5 - 10 km/h. Treeline temperature -4 °C.

Monday

Cloudy with isolated flurries. Variable alpine winds 0-5 km/h. Treeline temperature -2 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Avoid freshly wind loaded terrain features.
Wind slabs may be poorly bonded to the underlying crust.
Surface hoar distribution is highly variable. Avoid generalizing your observations.
Back off slopes as the surface becomes moist or wet with rising temperatures.

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.