Avalanche Forecast

Issued: Jan 16th, 2017 4:56PM

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

shorton, Avalanche Canada

Lizard-Flathead.

A sudden change in weather can have surprising effects on the snowpack. Conservative terrain use is key.

Summary

Confidence

Moderate - Freezing levels are uncertain on Tuesday

Weather Forecast

TUESDAY: Flurries with 3-5 cm of new snow, strong southwest winds, freezing level rapidly rising to around 1500 m.WEDNESDAY: Flurries with 5-15 cm of new snow, strong southwest winds, freezing levels around 1600 m.THURSDAY: Cloudy with isolated flurries, strong southwest winds, freezing levels around 1400 m.

Avalanche Summary

Several natural and human triggered size 1 wind slabs were reported on Monday. Over the weekend, widespread loose dry avalanches were reported, suggesting there's still lots of soft snow available to transport. Expect fresh wind slabs to form when the winds pick up on Tuesday.

Snowpack Summary

Increasing winds are causing widespread wind affect in exposed alpine and treeline terrain and forming touchy wind slabs on lee features. Last week, 20 cm of low density snow buried a plethora of old surfaces (wind scoured, old wind slabs, surface hoar up to 20 mm in sheltered terrain, and/or faceted old snow). Deeper in the snowpack, the mid-December persistent weak layer of facets has been more prominent and reactive in the Corbin area than areas closer to Fernie. The layer is generally considered dormant at the moment in deeper snowpack areas, but its status may change as the temperatures warm throughout the week.

Problems

Wind Slabs

Although there's not much new snow in the forecast, strong winds will transport loose surface snow and form touchy wind slabs on lee features.

Watch for signs of instability such as whumpfing, or cracking. Use ridges or ribs to avoid pockets of wind loaded snow.Avoid areas where the surface snow feels stiff or slabby.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Jan 17th, 2017 2:00PM