Avalanche Forecast

Issued: Jan 16th, 2019 5:40PM

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

shorton, Avalanche Canada

Lizard-Flathead.

Avalanche hazard will gradually increase over the next few days as snow accumulates. Triggering large avalanches remains possible on steep slopes with variable snow cover.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

WEDNESDAY NIGHT: Cloudy with clear periods, light southwest wind, alpine temperatures drop to -15 C.THURSDAY: Scattered flurries with 5-10 cm of low density snow, moderate southeast wind, alpine high temperatures around -10 C.FRIDAY: Mostly cloudy with isolated flurries, strong southwest wind, alpine high temperatures around -4 C.SATURDAY: 10-15 cm of snow, strong southwest wind, freezing level climbing to 1300 m, alpine high temperatures around -2 C.

Avalanche Summary

No new avalanches were reported on Wednesday.On Tuesday, several size 1-2 natural avalanches were reported in steep south facing alpine terrain (but their age is unknown).On Saturday, two large snowmobile triggered avalanches were reported on the Mountain Information Network. One was triggered on a thin, rocky, southwest facing feature near ridgecrest north of Fernie (see here for report). The other was triggered on a wind affected south facing slope at treeline in the Corbin area (see here for report).

Snowpack Summary

Recent warm alpine temperatures left crusty surfaces on southerly aspects, while the snow remained dry on northerly aspects. Old wind slabs and cornices could be lingering at higher elevations.In shallow snowpack areas, the base of the snowpack may still be composed of weak faceted grains. In deeper snowpack areas, the middle and lower portions of the snowpack are generally considered to be well-settled and strong.

Problems

Deep Persistent Slabs

The possibility of large releases remains in shallow snowpack areas. The chance of triggering is highest on steep rocky alpine slopes that have thin and/or variable snow cover.

Avoid steep slopes in shallow snowpack areas where triggering is more likely.Give rocky outcrops a wide berth in steep terrain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Wind Slabs

Watch for wind loaded slopes in the alpine and near ridgetops. New wind slabs may form over the next few days, while older wind slabs may still be triggered in steep lee terrain.

Stay well back from cornices.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: North, North East, East, West, North West.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Jan 17th, 2019 2:00PM