Avalanche Forecast

Issued: Jan 15th, 2022 4:00PM

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

Avalanche Canada bchristie, Avalanche Canada

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Avoid all avalanche terrain during periods of heavy snow, wind, or rain. 

The hazard ratings below represent the south end of the region and the areas around Stewart that are expected to receive heavier snow and rain fall. 

Summary

Confidence

Moderate - Uncertainty is due to the track & intensity of the incoming weather system. Recent weather patterns have resulted in a high degree of snowpack variability within the region.

Weather Forecast

Snow and rainfall amounts vary across the region. Check your local forecasts, ask your local mountain weather experts, and keep a close eye on local weather and snowpack conditions as you travel.

Saturday Night: Cloudy. 2-10 cm of snow expected. Moderate southwest wind. Freezing level dropping to between 500 m and 750 m. 

Sunday: Cloudy. 15-40 cm of snow expected with the higher amounts expected in the Skeena Valley, possibly pushing as far inland as Shames. Strong southwest wind, trending to extreme at higher elevations. Freezing level between 500 m and 750 m. 

Monday: Partly cloudy, clearing through the day. 5-15 cm of snow expected overnight, and a possible trace through the day. Moderate west wind, trending to strong northwest at higher elevations. Freezing level falling to around 500 m.

Tuesday: Scattered clouds. No new snow expected. Light variable winds. Freezing level at valley bottom. Treeline high around -7 °C.

Avalanche Summary

On Saturday northeast of Kitimat, evidence of several wet loose avalanches up to size 2 was reported above treeline. Riding conditions did not sound great. Check out the Mountain Information Network post here for more details. 

Also on Saturday, professional operations around the region reported several large, naturally triggered wet loose and storm slab avalanches, especially at treeline and below. The largest reported were size 3, in the Bear Pass area.  

  

On Friday, a few professional operations across the region reported large natural and explosive triggered loose wet avalanches at and below treeline as temperatures increased.

If you are getting out in the backcountry, and have conditions information, or even just good vibes and good photos to share, consider making a post on the Mountain Information Network (MIN). 

Snowpack Summary

By the end of the day on Sunday, total snowfall for this storm is forecasted to reach 40-80 cm. Expect storm slabs to be deeper and more reactive on north through east facing lee features due to moderate to extreme southwest winds. 

 In terrain around treeline, yesterday's rain moistened the surface snow. Freezing levels drop slightly during the day on Sunday, so that moist snow may now be frozen into a crust. This could improve avalanche hazard, but it will make riding conditions trickier. 

Low elevation terrain that sees moderate to heavy rainfall could continue to be unstable due to loose-wet avalanches or an upside down upper snowpack. 

The early December rain crust is up to 10 cm thick, down 100-200 cm in the snowpack, and exists to an average of 1400 m in elevation. While this layer had generally gone dormant in the region through the cold period, it still has the possibility of waking up and will be tested this week with the forecast warming event and ongoing snow accumulation. 

Extra caution is necessary while the snowpack undergoes substantial warming after a prolonged period of cold conditions. 

Terrain and Travel

  • Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
  • Watch for changing conditions today, storm slabs may become increasingly reactive.
  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • The more the snow feels like a slurpy, the more likely loose wet avalanches will become.
  • Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.

Problems

Storm Slabs

An icon showing Storm Slabs

Strong southwest wind is potentially increasing the reactivity of storm slabs in lee features. 

Freezing levels are variable over the region, and could depend on the intensity of the storm, so be ready for the snow/rain conditions to vary as you change elevations, and as the day progresses.

50-100 cm below the snow surface, Faceting from the prolonged cold temperatures may increase the chance of a storm slab in motion stepping down to the previous storm interface.  

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1.5 - 3

Persistent Slabs

An icon showing Persistent Slabs

Deeply buried weak layers in the snowpack will get tested this week with substantial warming and ongoing snow loading. While these layers have been dormant through the extended cold period, they have the potential to wake up this week, and smaller storm slab avalanches have the potential to step down to a deeper layer. Use extra caution and give the snowpack time to adjust to the warm conditions. 

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 3.5

Loose Wet

An icon showing Loose Wet

Some low elevation areas may see above zero temperatures and moderate to heavy rainfall.

This can rapidly weaken the snowpack, so stick to mellow slopes if you see large chunks of snow falling off of trees, pinwheeling or snowballing on slopes, or recent avalanches.  

Aspects: All aspects.

Elevations: Below Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 16th, 2022 4:00PM