Avalanche Forecast

Issued: Jan 25th, 2020 4:00PM

The alpine rating is considerable, 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 amounts and increasing winds will refresh our wind slab problem on Sunday. Seek out sheltered snow for the safest, best quality skiing and riding.

Summary

Confidence

Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.

Weather Forecast

Saturday night: Cloudy with isolated flurries and a trace of new snow. Light south winds, increasing in the morning.

Sunday: Cloudy with light flurries bringing about 5 cm of new snow, easing overnight. Light to moderate south winds, possibly strong at ridgetop. Alpine high temperatures around -4 with freezing levels to 1400 metres.

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

Tuesday: Cloudy with isolated flurries and a trace of new snow. Light south or southwest winds. Alpine high temperatures around -5.

Avalanche Summary

Reports from Friday included more observations of recent avalanche activity as well as a several new ski cut storm slabs and wind slabs, with a trend toward smaller releases. (size 1-1.5). All aspects were represented in reports, with some emphasis on north through east aspects.

There were numerous reports over the past few days of natural and human triggered avalanches. Most of these were size 1-2 storm and wind slab avalanches. All aspects and elevations were represented in reports, with some emphasis on north aspects for higher elevation releases. Similar activity was likely throughout the day on Friday.

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 heavily toward 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 is now moist or wet from warm temperatures, wet flurries, or rain up to at least 1500 metres.

The layer of surface hoar we have been tracking since late December has gained considerable strength in recent days. It is now buried roughly 90-130 cm deep in the Selkirks and 120-160 cm deep in the Monashees and exists primarily at treeline and below treeline. It may still be triggerable by a large load in shallower snowpack areas.

A facet/crust layer from late November may still be found near the bottom of the snowpack. This layer has been triggered by explosives in thinner alpine start zones in the Selkirks, but not in several weeks.

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 likely helped our recent storm snow settle and bond to the surface, however thicker, more reactive wind slabs are likely to be found at higher elevations. Light flurries and moderate to strong southwest winds should give this problem a refresh on Sunday.  

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 26th, 2020 5:00PM