Avalanche Forecast

Issued: Apr 17th, 2018 4:20PM

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

jasper snow safety, Parks Canada

Jasper.

Winter continues, along with the associated great skiing and multitude of avalanche problems. Don't let sunny skies and powder affect your decision making.

Summary

Weather Forecast

A shallow ridge of high pressure brings clearer weather while Arctic air to the north lingers until Wednesday, continuing to cool the local airmass.Moderate to strong SW winds Tuesday night will taper into Wednesday.Â Alpine temps will be Low -9, High -4, with the freezing level reaching 1800m mid-day.

Snowpack Summary

New soft slabs and varied degrees of wind effect found in all open areas. The upper snowpack is very sensitive to changes in temps, solar, or precipitation of any kind. Persistent slab will continue be a reoccurring problem, especially where no previous activity has been noted.

Avalanche Summary

Visibility improved over the day and we observed evidence of a wide spread cycle capturing all sorts of problems! Deep wide slabs from steep, rocky terrain. Numerous point releases. Soft slab releases from new loaded and wind pressed features.

Confidence

Problems

Wind Slabs

New snow and moderate to strong SW winds building fresh windslabs.

Use caution in lee areas. Recent wind loading has created wind slabs.If triggered the wind slabs may step down to deeper facet layers resulting in larger avalanches.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

Large cornices in all areas of the bulletin region. When failing these can trigger persistent instabilities and the subsequent avalanches are proving large and destructive.

Avoid travel on slopes that are exposed to cornices overhead.Minimize overhead exposure during periods of heavy loading from new snow, wind.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1.5 - 2.5

Persistent Slabs

40-100+ cm thick slabs overlie preserved facetted crystals on N aspects, these have been reactive recently.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Apr 18th, 2018 4:00PM