Avalanche Forecast

Archived

Feb 2nd, 2024–Feb 3rd, 2024

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.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

Cariboos, Blue River, McBride, Premier, Quesnel, Clemina, Esplanade, North Monashee, North Selkirk.

Expect challenging travel navigating refrozen surfaces and avalanche debris.

At higher elevations, evaluate how the new snow is bonding to the crust and avoid freshly wind-loaded areas.

Confidence

Moderate

Avalanche Summary

The natural avalanche cycle observed last week due to the warming event has tapered with cooling temperatures. Numerous size 2-4 wet slab, persistent slab, and wet loose avalanches were seen from all aspects and elevations.

Avalanche danger has decreased with cooling temperatures, but concern for persistent slab avalanches remains in isolated areas in the alpine where the snowpack was not significantly impacted by this warming.

Snowpack Summary

Cooling temperatures have left a surface crust of varying thickness at all elevations above 1000 m. At upper elevations, up to 10 cm of dry snow may exist on top of this crust. Below 1000 m, the snowpack remains wet and isothermal.

The stress of the new load (warm, wet upper snowpack) has produced avalanches failing down to the mid-January crust/facet layer (30-80 cm down) and the early December rain crust/ facet layer (100+ cm down) These layers may remain a concern in the alpine where they were not significantly impacted by rain and warm temperatures.

The lower snowpack is characterized by weak basal facets in many areas.

Weather Summary

Friday Night

Cloudy with light rain turning to snow, up to 5 cm accumulation. Alpine wind southwest 30 to 50 km/h. Treeline temperature dropping to -5 °C, freezing level falling to 800 m.

Saturday

A mix of sun and cloud with isolated flurries. Alpine wind west 15 to 30 km/h. Treeline temperature -5 °C.

Sunday

Mostly cloudy with isolated flurries. Alpine wind northeast 15 to 30 km/h. Treeline temperature -5 °C.

Monday

Cloudy with light flurries. Alpine wind southeast 15 to 40 km/h. Treeline temperature -5 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

A crust on the surface will help bind the snow together, but may make for tough travel conditions.
Wind slabs may be poorly bonded to the underlying crust.
Avalanche hazard may have improved, but be mindful that deep instabilities are still present.

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.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.