Avalanche Forecast

Issued: Jan 21st, 2019 4:32PM

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

mconlan, Avalanche Canada

South Coast Inland.

Wind slabs may still be reactive, as suggested by recent reports of small avalanches in wind-affected terrain. Travel conservatively, particularly if you notice snow with slab properties or see signs of instability.

Summary

Confidence

High -

Weather Forecast

MONDAY NIGHT: Cloudy skies, freezing level below valley bottom.TUESDAY: Cloudy with light snowfall, accumulation trace to 5 cm, moderate to strong southwest winds, alpine temperature -5 C, freezing level below valley bottom.WEDNESDAY: Cloudy with early-morning snowfall and clearing in the afternoon, accumulation 10 to 20 cm, moderate southwest winds, alpine temperature -4 C, freezing level rising to 1500 m in the afternoon.THURSDAY: Mix of sun and clouds, light northwest winds, alpine temperature 1 C, freezing level 2500 m.

Avalanche Summary

A few small (size 1) wind slab avalanches were triggered naturally in the region on Sunday.

Snowpack Summary

Around 20 to 40 cm of snow recently fell in the region with the most around Coquihalla. The snow fell with associated strong southwest winds, which has produced wind-affected snow surfaces in expose terrain. This recent snow fell onto a sun crust on southerly aspects, a temperature crust below around 1700 m on all aspects, and feathery surface hoar in areas sheltered by the wind at all elevation bands. The recent snow may not bond well to these layers.Below this, the snowpack is generally well-settled. In certain parts of the region, you may still find a weak layer of surface hoar buried about 60 to 100 cm in sheltered areas around treeline. This layer was recently triggered by a skier in the north of the region (see here). In the south of the region, snowpack tests suggest that avalanches could still be triggered within the layer (see here).

Problems

Wind Slabs

The recent snow may not bond well to underlying layers. The touchiest snow may be in exposed terrain, as the snow fell with strong winds. There is potential for triggered avalanches to step-down to deeper weak layers and produce larger avalanches.

Observe for the bond of the new snow to underlying surfaces.Watch for signs of instability such as whumpfing, cracking, or recent avalanches.Use caution in lee areas. Recent wind loading has created wind slabs.

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

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

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