Avalanche Forecast

Issued: Apr 2nd, 2018 5:08PM

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

Avalanche Canada simonhorton, Avalanche Canada

Storm slab problems are most likely in southern parts of the region that received more snow. Slopes with new snow above a crust and slopes with deep wind-blown pockets are the most suspect.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

TUESDAY: Mix of sun and cloud with some light flurries with accumulations of 1-3 cm, moderate to strong west wind, alpine high temperatures near -8 C, freezing level up to 1000 m.WEDNESDAY: Mostly cloudy, moderate southwest wind, alpine high temperatures near -5 C, freezing level up to 1200 m.THURSDAY: Light flurries with 2-5 cm, moderate southwest wind, alpine high temperatures near -12 C, freezing level at valley bottom.

Avalanche Summary

Small natural avalanches (size 1) were reported in the new snow on Monday. Ski cutting produced similar small avalanches on wind-loaded features, and explosives triggered one size 2 wind slab avalanche on an east aspect at 2300 m. This avalanche ran on a 60 cm deep crust layer.On Saturday, a large slab avalanche was observed in a burn around treeline. The avalanche was triggered by a snowmobile on a convoluted and convex terrain feature. Check out the MIN report here for more information and photos. Other wind slabs were noted in the region on all aspects.

Snowpack Summary

Northern parts of the region received 5-10 cm on Sunday night while up to 25 cm fell in southern parts of the region. The new snow sits above old wind slabs at higher elevations and above hard crust layers at lower elevations and on sunny aspects.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

An icon showing Storm Slabs
Storm slabs, as well as loose snow in sheltered areas, are not bonding well to underlying surfaces and will likely remain reactive at upper elevations. Large avalanches are possible on wind-loaded slopes.
Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.Use caution in lee areas in the alpine and treeline. Recent storm snow has formed touchy slabs.Choose well supported terrain without convexities.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

Valid until: Apr 3rd, 2018 2:00PM