Avalanche Forecast

Issued: Mar 17th, 2018 3:24PM

The alpine rating is low, the treeline rating is low, and the below treeline rating is moderate. Known problems include Loose Wet.

jmcbride, Avalanche Canada

Purcells.

Be aware of snow conditions that change with elevation and from one aspect to another. Pockets of wind slab may exist in the alpine while wet or moist snow may become a concern on sunny slopes, and at lower elevations.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain

Weather Forecast

SUNDAY: Mostly cloudy, flurries. Accumulation up to 5 cm. Ridge wind light, northwest. Alpine Temperature near -5. Freezing level 1500 m.MONDAY: Mostly cloudy, flurries. Accumulation 5-10 cm. Ridge wind light, west. Alpine Temperature near -5. Freezing level 1600 m.TUESDAY: Mostly cloudy, light flurries. Accumulation trace. Ridge wind light, southwest. Alpine temperature near -5. Freezing level 1600 m.

Avalanche Summary

Explosive control work on Friday produced size 1.5 slab avalanches averaging 20-60 cm deep on steep northerly features at treeline.Earlier in the week numerous wet loose avalanches were observed in the region to size 2.5 on sunny aspects. As well as both skier and sledder triggered wind slabs up to size 1.5 on south east to west aspects.

Snowpack Summary

A light dusting of new snow (5-10 cm) now covers a crust on all but high elevation northerly aspects which still hold loose, dry snow above a generally well-settled snow pack.A couple of layers buried in mid-late February (down around 40-100 cm) have shown limited reactivity of late. Persistent slabs have been triggered on shady aspects, where surface hoar and/or facets exist. Deeper persistent weak layers from January and December are generally considered dormant, but could wake up with a surface avalanche stepping down, cornice fall, or a human trigger in a shallow or variable-depth snowpack area. These layers consist of sun crust, surface hoar and/or facets. Facets also linger at the base of the snowpack.

Problems

Loose Wet

Watch for areas of moist or wet snow especially on steep, sunny slopes and near rocky outcrops or gullies.

Use caution above cliffs and terrain traps where small avalanches may have severe consequences.Use extra caution on slopes if the snow is moist or wet.

Aspects: North, North East, East, South East, South.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Mar 18th, 2018 2:00PM