Avalanche Forecast

Issued: Jan 26th, 2020 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs.

Avalanche Canada cgarritty, Avalanche Canada

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Light new snow inputs over the next couple of days may form thin new wind slabs, but also obscure recently formed slabs. Raise your guard as you gain elevation and keep seeking sheltered, low density snow.

Summary

Confidence

High -

Weather Forecast

Sunday night: Cloudy with continuing light flurries bringing up to 5 cm of new snow. Light to moderate south or southwest winds.

Monday: Cloudy with scattered flurries bringing about 5 cm of new snow. Light to moderate southwest winds. Alpine high temperatures around -5 with freezing levels to 1300 metres.

Tuesday: Cloudy with scattered flurries bringing up to 5 cm of new snow. Light southwest winds. Alpine high temperatures around -5.

Wednesday: Cloudy with flurries bringing 5-10 cm of new snow, increasing overnight.Light to moderate south winds, becoming strong at ridgetop and increasing overnight. Alpine high temperatures around-5.

Avalanche Summary

Reports from Friday and Saturday included numerous more observations of recent avalanche activity, as well as decreasing numbers of newer, smaller (size 1-1.5) storm slab and wind slab releases triggered with skier traffic and ski cutting. 

All aspects have been represented in recent reports, with some emphasis toward north and east aspects. An avalanche involvement in extreme terrain occurred in Glacier National Park on Saturday as well. Two skiers were caught in a size 2 slab release and one was partially buried. This marked up terrain image gives an idea of the event.

Wet loose releases from warm temperatures at lower elevations as well as sun exposure on steep high elevation slopes have also appeared throughout recent reports. Most have been smaller, but wet loose debris from one very large (size 3.5) avalanche was also observed in the northern Monashees on Friday. It scrubbed to ground and may have started as a slab release at around 1800 metres. Natural cornice triggers have also figured prominently in recent reports.

Looking forward, now that our recent snow has formed a more reliable bond with the old surface, areas of unstable snow should become increasingly limited to recently wind loaded pockets at higher elevations.

Snowpack Summary

Regular snowfall over the past week brought about 40-80 cm of snow to the region, with the greatest accumulations focused in the Monashees. 

Elevated, mainly south winds over the same period redistributed much of this snow in the alpine and upper treeline. Warm temperatures promoted slab formation with each snowfall as well as fairly quick transitions to settlement and bonding of the new snow. 

Surface snow recently became moist or wet from warm temperatures, wet flurries, or rain up to at least 1500 metres. New melt-freeze crusts may be found on the surface below this elevation, particularly where more pronounced melt occurred.

The layer of surface hoar we have been tracking since late December, now buried 90 to 170 cm deep, has gained considerable strength and is now considered dormant by professionals in the region. It remains a limited concern, potentially triggerable by large loads, in isolated areas of the Selkriks and the northern end of the Monashees. It exists primarily at treeline and just below treeline.

Terrain and Travel

  • Avoid freshly wind loaded terrain features.
  • Be alert to conditions that change with elevation, aspect and exposure to wind.

Problems

Wind Slabs

An icon showing Wind Slabs

Warm temperatures have helped our recent storm snow settle and bond to the surface, however thicker, more reactive wind slabs can be found at higher elevations. Light flurries will begin to hide these recently formed slabs on Monday.

Aspects: North, North East, East, South East, West, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 27th, 2020 5:00PM