Avalanche Forecast

Archived

Feb 1st, 2023–Feb 2nd, 2023

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 unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

New snow may not bond well to underlying crusts. Use caution as you transition into places where wind slab is forming and in features where storm slabs have settled and stiffened.

Confidence

Moderate

Avalanche Summary

A few new small wind slab avalanches have been reported in the region.

Backcountry users continue to report evidence of a significant avalanche cycle during the recent warm, wet, and windy weather last week. The majority of these avalanches were wind slabs, however, a number of avalanches stepped down to buried persistent layers, creating large, scary avalanches, like this one in the Telkwa area from Friday.

If you are out in the backcountry please consider filling out a Mountain Information Network report.

Snowpack Summary

There is now up to date 35 cm of storm snow over top of crusty surfaces from recent warming on January 25th. Some of this snow has been blown into wind slabs that can be easily triggered.

The mid and lower snowpack continues to bond and stabilize while a number of buried weak layers remain a concern and have produced a number of large recent avalanches.

Weather Summary

Wednesday night

Cloudy. 5 to 10 cm of new snow. Wind from the south at 25 km/h. Temperature -8 C.

Thursday

Cloudy. 10 cm of new snow. Wind from the south up to 30 km/h. Temperature -4 C.

Friday

Mostly cloudy. 5 cm of new snow. Wind from the up to 30 km/h. Temperature 0 C.

Saturday

Mostly cloudy. 5 cm of new snow. Wind from the up to 30 km/h. Temperature 0 C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Wind slabs are most reactive during their formation.
Wind slabs may be poorly bonded to the underlying crust.
Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.

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.

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.