Avalanche Forecast

Issued: Feb 9th, 2017 4:00PM

The alpine rating is high, the treeline rating is considerable, and the below treeline rating is considerable. Known problems include Wind Slabs, Loose Dry and Persistent Slabs.

mark herbison, Parks Canada

Jasper.

Avalanche Control along the Icefields Parkway is planned for Friday 1100 - 1700, expect delays.Strong winds and 20cm+ of snow have created dangerous avalanche conditions.

Summary

Weather Forecast

12cm of storm snow has fallen today with another 20cm forecasted by the end of Friday. Winds will be moderate from the SW, gusting to strong. Alpine temps to reach a high of -8.

Snowpack Summary

Light to moderate SW winds are building soft slab at treeline and above. The upper pack has several surface hoar and facet layers which will be layers of concern with the incoming storm. The mid-pack is facetted and weak, with depth hoar at its base.

Avalanche Summary

No road patrol today. Snowfall amounts adding up throughout the day.

Confidence

Intensity of incoming weather systems is uncertain on Friday

Problems

Wind Slabs

Moderate SW winds building windslab with recent storm snow and expected to bond poorly.

Keep an eye out for reverse loading created by an upslope storm.Use caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Loose Dry

Forecasted storm snow (~30cm) will fall over a poorly bonded, weak snow pack. Small sluffs have potential to entrain a lot of mass and grow in size quickly.

Be cautious of sluffing in steep terrain, particularly where the debris flows into terrain traps.Sluffs may trigger deeper instabilities.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2

Persistent Slabs

The Jan 17 interface or deeper layers might be woken up with the forecasted heavy snowfall and would result in large avalanches.

Be aware of thin areas that may propogate to deeper instabilites.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Valid until: Feb 10th, 2017 4:00PM