Avalanche Forecast

Issued: Jan 25th, 2019 3:01PM

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

Avalanche Canada jfloyer, Avalanche Canada

Anticipated warm weather will make triggering the most recent weak layer more likely.

Summary

Confidence

Moderate - Freezing levels are uncertain

Weather Forecast

FRIDAY NIGHT: A few flurries possible. Expected to stay cool overnight.SATURDAY: Dry. Temperatures showing a warming trend with an above-freezing level layer developing from approximately 1800-2400 m. Winds light northwesterly.SUNDAY: Light snow or rain (2-4 cm at higher elevations). Cooling rapidly through the day. Strong westerly winds.MONDAY: Dry. Freezing level at valley bottom. Light northwesterly winds.

Avalanche Summary

Several rider-triggered persistent slab and wind slab avalanches up to size 2 were reported on Tuesday, Wednesday and Thursday. The persistent slab avalanches were most prevalent between approximately 1500-1800 m, although some were noted at higher elevations, including into the alpine. Wind slabs were noted above 1800 m. Widespread dry loose sluffing from steeper terrain features has also been reported. As the upper snowpack becomes denser with expected warming, potentially surprising avalanches are expected to become more likely and widespread.Check out this MIN report for a great overview of conditions including photos.

Snowpack Summary

20-35 cm of recent new snow sits above a layer of large feathery surface hoar crystals and a sun crust. The new snow has been settling into a thin but reactive slab above this weak layer, with enhanced reactivity noted at elevations between 1500-1800 metres where the surface hoar is particularly well developed on all aspects. Until recently, in most sheltered places there was insufficient cohesion in the snow above the weak layer to form slab avalanches; reactivity was noted most in exposed areas where the wind had stiffened up the slab. Warmer temperatures are consolidating the upper snowpack are will likely make slab avalanches more widely triggerable.The middle and lower portions of the snowpack are generally well-settled and strong.

Problems

Persistent Slabs

An icon showing Persistent Slabs
20-35 cm of snow sits above a weak interface of surface hoar and sun crust. Where the snow has formed a cohesive slab it is reactive to human triggering, especially between 1500m-1800m.
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Watch for whumpfing, hollow sounds, and shooting cracks.use extra caution around steep open terrain features, such as cutblocks, gullies and cutbanks.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Jan 26th, 2019 2:00PM