Avalanche Forecast

Issued: Feb 13th, 2019 4:35PM

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

Avalanche Canada cgarritty, Avalanche Canada

Recently formed small wind slabs at higher elevations may remain reactive to human triggering. Sheltered lower elevations are likely to still hold the best skiing and riding conditions.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

Wednesday night: Cloudy with clear periods. Light to moderate southeast winds, increasing overnight.Thursday: Cloudy with sunny periods. Moderate to strong southeast or east winds. Alpine high temperatures around -14.Friday: Mainly cloudy with isolated flurries and a trace of new snow. Light east winds. Alpine high temperatures around -21.Saturday: Sunny with cloudy periods. Light northeast winds. Alpine high temperatures around -21, increasing overnight.

Avalanche Summary

Winds have been driving avalanche danger at higher elevations, redistributing recent snow accumulations into wind slabs. Skiers reported small natural wind slab releases, whumpfing, and shooting cracks on Thursday and Friday. A small (size 1) ski cut wind slab at 2100 metres was reported on Sunday. Most wind slabs are likely to be stabilized at this point, however, more recent small slabs in steep leeward features still need to be considered and managed.

Snowpack Summary

In the alpine and upper treeline, the upper snowpack is composed of successive layers of aging, wind-affected storm snow layers. The most recent wind slabs are likely to exist on on southwest aspects as a result of ongoing, predominantly northeast winds. The upper snowpack has also been faceting (becoming sugary) under the influence of recent cold temperatures at all elevations.Sheltered areas at lower elevations still hold around 20-30 cm of low density snow from a couple of recent snowfall events. Below this more recent snow, another 20-40 cm of older, faceted (sugary) storm snow overlies a widespread melt-freeze crust. In the central and northern parts of the region, it may sit on feathery surface hoar crystals in sheltered terrain at all elevations. In the south of the region, the remainder of the snowpack has been reported as well-settled.Around and north of Hazelton, 50 to 100 cm of snow may overlie two weak layers of surface hoar or sugary faceted grains.

Problems

Wind Slabs

An icon showing Wind Slabs
Relentless outflow winds have been redistributing snow at higher elevations for days. There is likely a mix newer, smaller, more reactive wind slabs as well as older, larger, more stubborn slabs to be found in wind-affected areas.
Back off from your line if the snow has become stiff or slabby from wind.Be careful around wind loaded pockets near ridge crests and roll-overs.Watch for patterns of wind loading if you venture into wind affected terrain.

Aspects: North, South, South West, West, North West.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Feb 14th, 2019 2:00PM