Avalanche Forecast

Issued: Mar 31st, 2018 4:25PM

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

mconlan, Avalanche Canada

South Rockies.

Expect to find wind slabs from recent snow that fell with strong winds. Observe for signs of instability before entering a slope, such as cracking, whumpfing, and avalanche activity.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

SUNDAY: Cloudy with light snowfall, accumulation 2 to 5 cm with possible localized higher amounts from convective flurries, light to moderate southwesterly winds, alpine temperature -8 C, freezing level 900 m.MONDAY: Cloudy with snowfall, accumulation 10 to 20 cm, light northeasterly winds, alpine temperature -15 C, freezing level 600 m.TUESDAY: Partly cloudy with light snowfall, light westerly winds, alpine temperature -8 C, freezing level 800 m.

Avalanche Summary

On Saturday, a large slab avalanche was observed in a treeline-like terrain feature in a forest burn, but at below treeline elevation. The feature is convoluted and of convective-nature. It is suspected that it was triggered by a snowmobiler. Check out the MIN report just south of Crowsnest Pass for photos.Â Other small wind slabs were noted in the region on all aspects.

Snowpack Summary

10 to 25 cm of new snow fell at higher elevations on Friday, with associated strong westerly switching to easterly winds. The precipitation fell as rain at lower elevations, which froze into a melt-freeze crust.About 50 cm deep, a crust is found up to 2200 metres. 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

Wind Slabs

Expect wind slabs in lee and cross-loaded terrain features recent avalanche activity has surprised riders even at relatively low elevations. Observe for signs of wind effect and slab properties before committing yourself into avalanche terrain.

Keep an eye out for localized areas of deeper snow accumulation, particularly on eastern slopes.Observe for signs of instability, such as cracking, whumpfing, and avalanche activity.Use caution in lee areas in the alpine and treeline where wind slabs are expected.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Apr 1st, 2018 2:00PM