Avalanche Forecast

Issued: Mar 19th, 2017 4:00PM

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

deryl kelly, Parks Canada

Jasper.

Check Alberta 511 for projected opening times and date for the Icefields Parkway (93N).

Summary

Weather Forecast

Storm exits and in comes a weak high pressure and inflow of cooler air for a few days. Alpine temps to dip below -15 for Monday morning with clearing skies. Strong solar influence can be expected and will likely wake up an already stressed snowpack on any south aspect, especially below treeline as freezing levels are again expected to rise to 2000m

Snowpack Summary

+50cm HST this month redistributed with Mod SW winds. Deeply loaded (100+ cm) lee areas with unpredictable spacial variability. Buried localized solar, rain and melt-freeze crusts, up to 2000+m on S and 1600m in the N asp. New snow weakly bridging a faceted older snow pack. Morphing interfaces scattered, at depth through the midpack to ground.

Avalanche Summary

Historically quiet avalanche paths running full path and hitting the highway. Historically active paths, acting normal and hitting the highway.

Confidence

Problems

Wind Slabs

50+cm of storm snow over the week has formed a dangerous windslab. Wide crowns up to 2m deep have been seen from Maligne to Parkers area. Moderate to strong SW winds and warm temps will keep this layer very active.

It is a good time to stay within the boundaries of a ski resort.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

2 - 3

Deep Persistent Slabs

The widespread observations of large and deep avalanches indicates strongly that many of these events are from this instability. Increased loading and warm temperatures will keep this layer active.

Be careful with low angle slopes that may not normally be a concern.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 4

Valid until: Mar 20th, 2017 4:00PM