Avalanche Forecast

Issued: Jan 25th, 2020 5:00PM

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

Avalanche Canada dsaly, Avalanche Canada

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Recent winds have promoted wind slab development at upper elevations, use caution around wind loaded features and deep deposits of fresh snow.

Summary

Confidence

Moderate - The number, quality, or consistency of field observations is good, and supports our confidence.

Weather Forecast

SATURDAY NIGHT: Cloudy with isolated flurries. Alpine low temperature -2 C. South wind 20-30 km/hr. Freezing level 1200 m.

SUNDAY: Flurries, 5-10 cm. Alpine temperature -2 C. Southwest wind 20-40 km/hr. Freezing level 1500 m.

MONDAY: Flurries, up to 10 cm. Alpine temperature -5 C. Southwest wind 20-35 km/hr. Freezing level 1100 m.

TUESDAY: Flurries and snow, 10-20 cm. Alpine temperature -3 C. Southwest wind 20-40 km/hr. Freezing level 1400 m.

Avalanche Summary

On Friday, storm slab avalanches up to size 2 were triggered by explosives, skiers, and failed naturally. 

On Thursday, skiers triggered size 1-2 storm slab avalanches including this MIN report of a skier triggered avalanche at Kootenay Pass. This avalanche was triggered on a south aspect at treeline and ran for a long distance above the recently buried crust. Several loose wet avalanches were reported on southerly aspects below 2000 m.

No persistent slab avalanches have been observed since January 14, suggesting deep weak layers have become difficult to trigger under the current conditions.

Snowpack Summary

20-40 cm of snow over the past few days has settled with warm temperatures and been impacted by southwesterly winds.This new snow overlies a couple of crust layers that formed between January 19-24, this is the interface recent storm snow avalanches failed on. With the recent warm temperatures, moist surface snow was reported up to 1700 m, a crust may form as temperatures cool.

We have been tracking two layers over the past month: a layer of surface hoar buried 80-120 cm below the surface and faceted crystals and crusts near the bottom of the snowpack in certain parts of the region (especially western areas such as the Rossland Range and Boundary region). Both of these layers have shown signs of being less reactive over the past 10 days.

Terrain and Travel

  • Be careful as you transition into wind affected terrain.
  • Approach lee and cross-loaded slopes with caution.
  • Be alert to conditions that change with elevation.

Problems

Wind Slabs

An icon showing Wind Slabs

Warm temperatures have likely helped the recent storm snow settle and bond, southerly winds are redistributing snow into slabs at treeline and above.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

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