Avalanche Forecast

Issued: Mar 1st, 2017 4:59PM

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

Avalanche Canada cgarritty, Avalanche Canada

Look for a range of touchy avalanche problems developing as the stormy weather continues. Lower elevations won't be immune.

Summary

Confidence

Moderate -

Weather Forecast

Thursday: Flurries bringing 5-10 cm of new snow. Winds moderate to strong from the southwest. Freezing level to 1300 metres with alpine temperatures of -7.Friday: Periods of snow bringing another 10-15 cm of new snow. Winds strong to extreme from the southwest. Freezing level to 1300 metres with alpine temperatures of -5.Saturday: Mainly cloudy with isolated flurries and a trace of new snow. Winds moderate from the southwest. Freezing level to 1200 metres with alpine temperatures of -6.

Avalanche Summary

Reports from Tuesday include natural Size 1 cornice, storm slab, and wind slab releases, as well as two remote triggered Size 1 wind slabs. One storm slab and one cornice were observed releasing naturally to Size 2. These occurrences took place on a range of aspects, but most of them shared unsupported, steeper, alpine terrain as a common feature.On Sunday, small avalanches in the new snow were reported including natural and skier triggered size 1 wind slabs on a variety of aspects. Sluffing in steep terrain was widespread. A few size 2 natural avalanches were also reported in alpine terrain, potentially releasing on the mid-February interface 30-40 cm deep. Looking forward, ongoing snowfall and increasing winds are expected to promote new wind slab activity at treeline and in the alpine on Thursday. Increasing caution is also warranted at lower elevations where new snow is building both slab and loose dry avalanche hazards.

Snowpack Summary

A wide-ranging 10-37 cm of new snow fell over the region over Tuesday night, with the greatest accumulations occurring in the eastern Monashees. The new snow has buried fairly widespread faceted surface snow as well as more isolated surface hoar to 4mm. A thin sun crust may exist below the new snow on steep solar aspects. About 40-80cm below the surface you'll likely find the mid-February interface which is composed of a thick rain crust up to about 1800 m, sun crusts on steep solar aspects, and spotty surface hoar on shaded aspects. This layer could develop into a persistent slab problem once the snow above it settles into a stiffer slab. The mid and lower snowpack are generally well settled and stable.

Problems

Storm Slabs

An icon showing Storm Slabs
Ongoing snowfall and strong southwest winds will form reactive wind slabs at treeline and in the alpine on Thursday. Both slab and loose dry avalanche hazards are also increasing as snow piles up at lower elevations where the winds are weaker.
Be alert to conditions that change with elevation.Stay off recent wind loaded areas until the slope has had a chance to stabilize.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 2

Valid until: Mar 2nd, 2017 2:00PM