Avalanche Forecast

Issued: Feb 24th, 2018 4:22PM

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

Avalanche Canada mconlan, Avalanche Canada

Storm slabs have formed with recent snowfall. Expect them on all aspects with thicker slabs in lee features, loose dry snow in sheltered areas, and looming cornices on ridgelines. Treat the hazard higher if you see more snow than forecasted.

Summary

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

SATURDAY NIGHT: Cloudy with snowfall, accumulation 10 to 20 cm, strong southwesterly winds, alpine temperature -10 C, freezing level below valley bottom.SUNDAY: Cloudy with intermittent snowfall, accumulation 5 to 10 cm in the south of the region, light to moderate westerly winds, alpine temperature -13 C, freezing level near 500 m.MONDAY: Partly cloudy, light westerly winds, alpine temperature -12 C, freezing level 700 m.TUESDAY: Mostly cloudy with light snowfall, accumulation 5 cm, light to moderate westerly winds, alpine temperature -10 C, freezing level 800 m.

Avalanche Summary

Cornices were triggered by explosives in the north of the region on Saturday, which produced up to size 2 avalanches.Expect natural and human-triggered avalanche activity to increase with the recent snowfall and strong winds.

Snowpack Summary

Around 10 to 20 cm of storm snow fell Friday night and another 15 to 30 cm is forecasted Saturday night into Sunday. These storms have had strong westerly winds associated with them. Expect touchy storm slabs on all aspects with thicker slabs in lee features. All of this snow fell on previously wind-affected surfaces. The new snow may not bond well to these surfaces and could be reactive to both natural and human triggers.In the southern parts of the region, a widespread crust exists around 40 to 80 cm deep. Well-consolidated snow exists below the crust.Also make note of cornices at ridgeline. Variable winds in the past month have produced cornices on all aspects. They will become touchier as they grow in size, as temperatures rise, and as the sun packs a strong punch on clear days. Stand well back of them and avoid them from below!

Problems

Storm Slabs

An icon showing Storm Slabs
Storm slabs have formed with new snow and strong winds. These slabs may not bond well to underlying surfaces.  Thicker slabs are expected around Coquihalla and Manning. Stick to low-angled, sheltered terrain and give the snow time to stabilize.
Watch for signs of instability, such as avalanche activity, whumpfs, and shooting cracks.Approach lee and cross-loaded slopes with caution.Use caution above cliffs and terrain traps where small avalanches may have severe consequences.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Feb 25th, 2018 2:00PM