Avalanche Forecast

Issued: Jan 16th, 2015 8:17AM

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

pgoddard, Avalanche Canada

Northwest Inland.

Give recently wind-loaded slopes a wide berth.

Summary

Confidence

Fair - Due to the number of field observations

Weather Forecast

Expect around 5 cm snow on Saturday with moderate to strong SW winds and the freezing level near 800 m. A second system is forecast to affect the area on Sunday, petering out slowly on Monday.Â A further 5-10cm snow is expected, with strong S-SW winds and freezing level around 600 m.

Avalanche Summary

Skiers triggered size 1 slabs on wind-loaded features at treeline on Friday. Further west there have been reports of large natural avalanches on N and NW facing slopes around 1800m within the last couple of days.

Snowpack Summary

Strong southerly winds are building wind slabs, generally depositing snow on N and NE aspects. A rain crust is still out there up to 1600m and a melt freeze crust to 1850m. Keep in mind a surface hoar layer reported to be 15 to 20cm below the surface in areas protected from the wind. We're watching the December crust, but we haven't seen any activity on it recently, most likely because it hasn't received a significant load on it. Near the base of the snowpack is a November crust-facet combination that could remain problematic for some time.

Problems

Wind Slabs

Wind slabs continue to build at ridge top and treeline elevations. Keep an eye out for cornices too.

Choose well supported terrain without convexities.>Use ridges or ribs to avoid pockets of wind loaded snow.>Avoid freshly wind loaded features.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Persistent Slabs

A persistent weak layer is widely variable in depth. It could be triggered by a person or snowmobile hitting a sweet spot, creating a surprisingly large avalanche.

Be aware of the potential for large, deep avalanches.>Use caution around convexities, ridge crests, rock outcroppings and anywhere else with a thin or variable snowpack.>Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 6

Valid until: Jan 17th, 2015 2:00PM