Avalanche Forecast

Issued: Jan 18th, 2019 4:04PM

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

Rupert wedgwood, Parks Canada

Jasper.

Incoming snow and strong SW winds will increase the avalanche danger at all elevations

Summary

Weather Forecast

Incoming snow with strong SW winds are forecasted for the next 24hrs. Snowfall amounts continue to be down graded now at 10-15cm overnight and Saturday afternoon. Strong to extreme SW winds will redistribute the snow onto lee features. Temps at treeline will be -6C but cooling will occur as the storm passes and the winds decrease into the evening.

Snowpack Summary

Last weeks surface hoar and suncrust will be buried under the incoming new snow. These layers will be the new focus of concern. The additional load may well awaken the deeply buried basal instabilities and wind slab activity can be expected at treeline and above.

Avalanche Summary

No new avalanche observations were report from a team in Parkers Ridge area todayBe a part of the Avalanche Forecasting team by reporting your field trip this weekend on Avalanche Canada's Mountain Information Network.

Confidence

Problems

Deep Persistent Slabs

The new snow will increase the reactivity of this deeply buried problem. An avalanche of this nature would be large with severe consequences.

Avoid steep convexities or areas with a thin or variable snowpack.Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 4

Wind Slabs

The incoming new snow and strong SW winds will produce windslabs at all elevations. Beneath the slab is a widespread surface hoar layer on most aspect from treeline to the valley bottom. Also near treeline on southerly slopes is a buried sun crust.

If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Avoid open slopes and convex rolls at treeline where buried surface hoar may be preserved.

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

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1.5 - 2.5

Valid until: Jan 19th, 2019 4:00PM