Avalanche Forecast

Issued: Jan 16th, 2022 4:00PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is high. Known problems include Storm Slabs.

Avalanche Canada ahanna, Avalanche Canada

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Avalanche danger will increase as new snow and wind build fresh, reactive storm slabs. The HIGH danger rating reflects precipitation amounts in the southern arm of the region. Elsewhere, if you see less than 25 cm of new snow, consider avalanche danger to be one step lower.

Summary

Confidence

Moderate - Uncertainty is due to the track & intensity of the incoming weather system. We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

Heaviest snowfall amounts are forecast for the south of the region, including Renshaw and Torpy riding areas.

Sunday night: Snowfall 30-40cm in the south, 5-15 cm elsewhere. Strong westerly wind. Freezing levels around 1400 m in most areas and 1800 m on the Alberta side.

Monday: Snowfall 25 cm in the south, 5-15 cm elsewhere. Strong westerly wind. Freezing levels dropping to valley bottom in the late afternoon.

Tuesday: Sunny. Light NW wind. Treeline high around -12 °C. Freezing level valley bottom.

Wednesday: A mix of sun and cloud. Moderate SW wind. Treeline high around -8 °C. Freezing level valley bottom.

Avalanche Summary

On Friday, the Avalanche Canada field team reported several natural size 1 and two size 2 storm slab avalanches in the alpine on northeast aspects in the Renshaw area, mostly releasing under cornices. These were failing in the storm snow down roughly 15-30 cm. Their MIN report has some good photos showing the type of terrain where these avalanches were occurring. A few other natural wind slab avalanches up to size 2 were reported on north and east aspects further north in the region. Explosives were triggering storm slabs up to size 2 failing down 20-30 cm. On Thursday, a loose wet avalanche was reported on a SE aspect at 1800 m east of Prince George which was likely solar triggered. 

Snowpack Summary

New snow and strong wind are building fresh storm slabs. Heaviest snowfall is forecast for the south of the region, where 20-30 cm is forecast per 12 hour period. The new snow accumulates over previously reactive wind slabs at upper elevations and over a layer of surface hoar in sheltered areas.

Below around 1500 m, a thin breakable crust or two may be present in the upper snowpack from the recent warm weather. A layer of faceted snow can likely be found down around 40-100 cm from the cold period at the end of December but it has not been reactive recently and does not seem to be creating an avalanche problem in most of the region. 

The early-December crust/facet interface can typically be found down 50-150 cm but has been dormant recently and is no longer expected to be creating an avalanche problem in the region. The base of the snowpack is composed of crusts and weak faceted grains, particularly in thin snowpack areas east of the divide. 

Terrain and Travel

  • Storm slab size and sensitivity to triggering will likely increase through the day.
  • Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
  • Make observations and assess conditions continually as you travel.
  • Dial back your terrain choices if you are seeing more than 25cm of new snow.

Problems

Storm Slabs

An icon showing Storm Slabs

New snow and wind are forming fresh storm slabs. Storm slabs are most likely to be reactive in wind loaded features and where the new snow sits over surface hoar or a crust.

At low elevations where precipitation falls as rain, the likelihood of loose wet avalanches will increase as rain soaks the snowpack.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Almost Certain

Expected Size

1.5 - 2.5

Valid until: Jan 17th, 2022 4:00PM