Avalanche Forecast

Issued: Feb 8th, 2023 4:00PM

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

Avalanche Canada cgarritty, Avalanche Canada

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Take an assessment mindset with you to find out how far inland the storm is penetrating. Whether it's 10-15 cm and wind slabs forming in specific leeward pockets or 15-25 cm and a widespread touchy storm slab, it will be a good day to find some sheltered terrain away from cranking winds, overhead hazards, and the most active avalanche conditions.

Summary

Confidence

Low

Avalanche Summary

Tuesday's reports included observations of a very large (size 3.5) natural deep persistent slab avalanche that occurred in the Babines over the recent stormy period. This speaks to the importance of conservative terrain selection through this period of active weather. Several less surprising small to large (size 1-2.5) naturals were observed in steep leeward terrain in the same area.

Observations from Monday in the snowier southwestern part of the region show our recent storm snow reacting to ski cutting, which produced numerous small (up to size 1.5) storm slabs on steep slopes at treeline and below with crowns up to 40cm. Isolated natural releases were also observed in the alpine.

All of these occurrences give an indication of the character of avalanches we might see through this next storm pulse.

If you are out in the backcountry, please share your observations to the Mountain Information Network!

Snowpack Summary

An uncertain 10-25 cm of new snow could accumulate in the region by end of day Thursday with the heaviest amounts expected in the southwest of the region. Forecast strong south winds will promote new slab formation over the day.

The new snow will add to 50-60 cm of recent storm snow that has been getting continuously blown into wind slabs by southwest winds at treeline and above. The growing storm total sits on a crust from the warming event on January 25th and the bond at this interface is still in question, especially with forecast loading from new snow and wind.

The mid and lower snowpack continues to bond and stabilize. A few concerning weak layers can still be found in the top meter of the snowpack including a surface hoar layer from early January and a crust from late December.

Weather Summary

Wednesday night

Cloudy with increasing snowfall bringing 5 -15 cm of new snow, heaviest in the southwest of the region. Winds becoming strong southeast.

Thursday

Cloudy with continuing flurries bringing 5-10 cm of new snow, again greatest in the southwest. Strong south winds easing to moderate over the day. Treeline high temperatures around -4 with freezing levels rising to 1000 m.

Friday

Diminishing cloud and isolated flurries. Storm totals of 15-30 cm. Moderate southwest winds shifting west. Treeline high temperatures around -5.

Saturday

Cloudy with scattered flurries and a trace of new snow. Strong southwest winds easing over the day. Treeline high temperatures around -7.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Make observations and assess conditions continually as you travel.
  • Use increased caution at all elevations. Storm snow is forming touchy slabs.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.

Problems

Storm Slabs

An icon showing Storm Slabs

Continuous snowfall and high southwest winds will make for fresh surface instabilities Thursday, but uncertain snowfall amounts make for uncertainty about the severity of the problem. Expect touchy new wind slabs in leeward terrain features with up to 15 cm of new snow. More than that and it's time to factor in a widespread storm slab affecting all steep terrain. The latter is more likely in the southwest of the region.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A number of buried weak layers remain possible to trigger. These layers appear to be most problematic in upper treeline and alpine elevations, in shallow, variable, rocky start zones. A sensitive storm slab or wind slab overlying this problem could serve as the perfect trigger for a destructive step-down avalanche.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3.5

Valid until: Feb 9th, 2023 4:00PM

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