Avalanche Forecast

Issued: Mar 31st, 2018 3:28PM

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

Avalanche Canada simonhorton, Avalanche Canada

Stick to small supported terrain features and give the storm snow time to heal. Be extra suspect of wind-loaded slopes.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

SUNDAY: Flurries with 5-15 cm of new snow, light wind, freezing level up to 700 m, and alpine high temperatures near -8 C.MONDAY: Mix of sun and cloud with light wind, freezing level up to 600 m, and alpine high temperatures near -10 C.TUESDAY: Moslty cloudy with scattered flurried (2-4 cm of snow), moderate southwest wind, freezing level up to 1000 m, and alpine high temperatures near -6 C.

Avalanche Summary

On Friday, a natural size 2.5 storm slab avalanche was reported west of Valemount on a northwest aspect at 2400 m.On Thursday, a few size 2 natural storm slab avalanches were reported on north and east aspects. A cornice fall triggered a large slab avalanche with a 100 cm crown on a north aspect at 2600 m. A skier also remotely triggered a size 1 wind slab on a southeast aspect at 1900 m.These avalanches follow a widespread natural avalanche cycle that occurred on Tuesday and Wednesday. Storm slabs in the size 2-3 range were reported on all aspects between 1700 and 2500 m. Southerly aspects were the most reactive with numerous large and very large (size 2.5-3.5) avalanches running on a recently buried sun crust.

Snowpack Summary

Another 20-30 cm of snow on Friday brings last week's total to 60-100 cm. Storm snow was accompanied with strong west wind, forming reactive slabs at higher elevations.The storm snow sits on an interface buried in late-March that consist of crusts at low elevations and on south aspects, and surface hoar on shaded aspects at higher elevations.Persistent weak layers from early January and mid-December are still being reported by local operators, but are generally considered dormant.

Problems

Storm Slabs

An icon showing Storm Slabs
Human-triggered storm slabs remain a concern on wind-affected features and on south aspects where they sit above buried sun crusts.
Minimize exposure to steep planar south-facing slopesChoose well supported terrain without convexities.Avoid freshly wind loaded features.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2.5

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