Avalanche Forecast

Issued: Feb 24th, 2019 5:03PM

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

Ruari Macfarlane, Parks Canada

Jasper.

In addition to listed problems, be vigilant for isolated windslabs in the Columbia Icefields region.

Summary

Weather Forecast

Cold, static High pressure continues. Monday: Mainly Sunny, Treeline Low -24, High -18, Light winds. Tuesday: Sunny, Low -25, High -17, Moderate Easterly Alpine winds easing to Light.Wednesday: Winds remain subdued, but cloud is possible and temperatures finally climb, possibly to -10. Mountain weather forecast available at Avalanche Canada.

Snowpack Summary

Towards the Icefields, the alpine is wind affected. The Jan 18 surface hoar layer (down 40cm) has faceted away in most places, but shows isolated sensitivity at treeline and below in the Icefields region. The midpack is mainly supportive, over depth hoar in shallow areas. Although structurally weak, this layer has been generally dormant lately.

Avalanche Summary

No notable avalanches were seen on Sunday, only evidence of previous small (size 1) loose dry and windslab avalanches from the previous several days. On Thursday near Nigel Pass, forecasters observed a small natural cornice fall trigger a size 1.5 Deep Persistent slab avalanche. This occurred on a steep, unsupported North aspect, at 2700m.

Confidence

Due to the number of field observations

Problems

Deep Persistent Slabs

Although the basal weakness (depth hoar) is generally dormant, with no recent natural loading of the snowpack, these may still be possible in isolated places. Steep, unsupported, and thin depth are factors to be wary of, as are cornices overhead.

Minimize exposure to terrain traps where the consequences of an avalanche could be serious.Be cautious in shallow snowpack areas where triggering is more likely.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely

Expected Size

1.5 - 3

Loose Dry

Isolated to steep terrain where surface snow doesn't show signs of previous wind affect : all elevations at the north end of the bulletin region, but only lower elevations in the Columbia Icefields region

Minimize exposure to terrain traps where the consequences of an avalanche could be serious.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Feb 25th, 2019 4:00PM