Avalanche Forecast

Issued: Jan 21st, 2019 5:02PM

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

dboucher, Avalanche Canada

North Columbia.

New snow will continue to accumulate above the newly buried weak layer. Thick wind slabs have been reported in the alpine and thinner but more widespread slabs over layer of surface hoar are still reactive at mid and lower elevations.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain on Wednesday

Weather Forecast

MONDAY NIGHT: Cloudy with isolated flurries, moderate winds from southwest, alpine temperature -12 C, freezing level at valley bottom.TUESDAY: Flurries, snow accumulation ranging from 5 to 10 cm, moderate southwest winds, alpine temperature -6 C, freezing level at 900 m.WEDNESDAY: Mainly cloudy with scattered flurries, snow accumulation ranging from 3 to 5 cm, light to moderate west winds, freezing level at 1100 m.THURSDAY: Mainly cloudy with isolated flurries, light to moderate west winds, alpine temperature -5 C, freezing level at 900 m.

Avalanche Summary

Numerous natural and skier-triggered storm slabs avalanches size 1 to 2 were observed on Sunday.Â These avalanches were running on the newly buried weak layer, especially between 1500 to 1800 m where surface hoar was most prevalent.Â In the alpine, deeper wind slabs avalanches have been observed mostly on north slopes loaded by recent moderate to strong south winds.

Snowpack Summary

15-25 cm of new snow from the weekend continues to settle above a layer of large surface hoar crystals and sun crusts. The new snow has been settling into a thin but reactive slab above this weak layer, with enhanced reactivity noted at elevations between about 1500-1800 metres, where surface hoar is particularly well developed.Although the surface hoar is less prevalent in the alpine, strong southerly winds during and immediately after the storm formed deeper and similarly reactive deposits on lee slopes. New snow deposits that overlie sun crust on steep, south-facing slopes may be especially touchy.The middle and lower portions of the snowpack are generally well-settled and strong.

Problems

Storm Slabs

15-25 cm of new snow has been blown around into reactive slabs at higher elevations. Lower down, a layer of surface hoar and crusts beneath the new snow is making slabs extra touchy.

Watch for signs of instability such as whumpfing, cracking and recent avalanches..Expect to find deeper, reactive wind slabs as you transition into wind affected terrain.Be cautious around open terrain features, such as cutblocks, gullies, and cutbanks.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 22nd, 2019 2:00PM