Avalanche Forecast

Archived

Mar 11th, 2024–Mar 12th, 2024

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Regions

Northwest Inland, Kispiox, Microwave-Sinclair, North Bulkley, South Bulkley, South Bulkley, South Bulkley, Telkwa.

Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency. Choose low-consequence terrain and avoid exposure to overhead hazard.

Confidence

Moderate

Avalanche Summary

Several avalanches surprised skiers across the region over the weekend. Some were quite large and were remotely triggered from a distance, indicating a touchy snowpack over a persistent weak layer. Many groups recently traveling in the backcountry have also reported signs of instability like whumpfing and shooting cracks.

For more information, click on the photos below.

Snowpack Summary

Expect to find up to 25 cm of soft snow in wind-sheltered and shady areas. This snow covers wind-affected surfaces or a crust on sun-exposed slopes and at lower elevations. A layer of weak, faceted crystals over a crust, or surface hoar, is the primary layer of concern, buried around 40 to 80 cm.

A sun crust may have formed on the surface on steep south and west-facing slopes, and snow will be heavier and possibly moist or crusty at lower elevations.

Weather Summary

Monday Night

Cloudy with 2 to 5 cm of new snow expected. 40 to 50 km/h southeast ridgetop wind. Treeline temperatures around - 3 °C.

Tuesday

Partly cloudy, with 2 cm of new snow expected. 30 to 40 km/h southwest ridgetop wind. Treeline temperatures around -3 °C. Freezing level rising to 1000 m.

Wednesday

Cloudy, with 2 to 5 cm of new snow expected. 50 to 60 km/h southwest ridgetop wind. Treeline temperatures around 0 °C. Freezing level rising to 1200 m.

Thursday

Cloudy, with 2 to 5 cm of new snow expected. 50 to 60 km/h southwest ridgetop wind. Treeline temperatures around +2 °C. Freezing level rising to 1500 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Remote triggering is a concern, watch out for adjacent and overhead slopes.
If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.
Back off if you encounter whumpfing, hollow sounds, or shooting cracks.

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.

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.