Avalanche Forecast

Issued: Apr 1st, 2018 3:56PM

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

mconlan, Avalanche Canada

South Rockies.

Substantial snowfall could accumulate by Monday morning. Treat the hazard as higher if you find more than 30 cm of new snow. Storm slab avalanches are likely -- conservative decision-making is recommended.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain

Weather Forecast

MONDAY: Cloudy with snowfall, accumulation 10 to 20 cm and possible localized higher amounts from convective flurries, light northeasterly winds, alpine temperature -15 C, freezing level below valley bottom.TUESDAY: Partly cloudy with light snowfall, accumulation 1 to 3 cm, light westerly winds, alpine temperature -9 C, freezing level 800 m.WEDNESDAY: Mostly cloudy, light southwesterly winds, alpine temperature -7 C, freezing level 1300 m.

Avalanche Summary

On Saturday, a large slab avalanche was observed around treeline in a forest burn. The feature is convoluted and of convective-nature. It is suspected that it was triggered by a snowmobiler. Check out the MIN report here for more information. Other wind slabs were noted in the region on all aspects.

Snowpack Summary

Around 10 to 20 cm of new snowfall is expected in the region. The new snow will fall on wind slabs at higher elevations and a melt-freeze crust on sunny aspects and all aspects at low elevations.Numerous crusts are found around 60 to 80 cm deep up to 2200 m. At a similar depth, a layer of surface hoar is found on shaded aspects at treeline in parts of the region.The midpack is well-settled and strong. This overlies sugary facets in thin snowpack areas.

Problems

Storm Slabs

Expect to find storm slabs where substantial snowfall accumulates. Loose snow may be found in sheltered areas. Be disciplined: observe for slab properties and the bond with the old snow surface before committing into avalanche terrain.

Use caution in lee areas in the alpine and treeline where wind slabs are expected.Observe for signs of instability, such as cracking, whumpfing, and avalanche activity.Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Apr 2nd, 2018 2:00PM