Avalanche Forecast

Issued: Jan 16th, 2018 4:52PM

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

simonhorton, Avalanche Canada

Northwest Coastal.

Dangerous storm slabs will develop this week. Stick to conservative terrain during the storm.

Summary

Confidence

Moderate - Intensity of incoming weather systems is uncertain

Weather Forecast

WEDNESDAY: Flurries start Thursday night delivering 20-40 cm of snow by Wednesday afternoon, strong south wind, freezing level around 700 m.THURSDAY: Another 10-30 cm of snow, strong south winds, freezing level steady at 700 m.FRIDAY: Light flurries, moderate southeast winds, freezing level around 500 m.

Avalanche Summary

No recent slab avalanches have been reported. A natural cycle of wet loose avalanches (up to size 2.5) occurred on steep solar aspects over the weekend. Expect a spike in activity with the incoming storm.

Snowpack Summary

New storm slabs are developing, with extra thick and reactive slab in lee areas. The new snow is falling on a mix of old wind slabs and temperature crusts left over from the weekend. Professionals have been monitoring a few layers in the upper snowpack, including crusts and surface hoar layers buried 40-80 cm below the surface. Although these layers have been reactive in recent snowpack tests, they have not produced avalanches lately. The lower snowpack is generally strong, with the exception of areas around Stewart and further north where a basal crust and facets exist.

Problems

Storm Slabs

Expect 20-40 cm of new snow by Wednesday afternoon with strong winds. Touchy storm slabs will likely develop in steep terrain throughout the day.

Minimize exposure during periods of heavy loading from new snow and wind.Use conservative route selection, choose moderate angled and supported terrain with low consequence.Avoid steep convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2.5

Valid until: Jan 17th, 2018 2:00PM