Avalanche Forecast

Issued: Nov 23rd, 2013 8:05AM

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

catherine brown, Parks Canada

Glacier.

The Winter Permit System comes into effect on Tuesday, November 26th. Click here: Winter Permit Information, for further info.

Summary

Weather Forecast

Freezing levels will to rise to 1800 m today, with 0 deg temps for the Alpine and an inversion setting up. Ridge top winds will be light with no snow in the forecast. Similar weather is forecast for the park tomorrow, with gusting winds to 55 km/h. This stable weather pattern, with no precipitation, will continues through the forecast.

Snowpack Summary

Last week's storm snow is continuing to settle. The November 12th surface hoar layer is buried between 50 and 110cm. Its distribution is valley dependant. It had been observed up to 2500m on Mt Abbott in the Asulkan Valley possibly explaining the occurrence of large natural avalanches to size 3.5 running off the Dome.

Avalanche Summary

Solar induced slides on south through west facing slopes are possible today if the sun stays out this afternoon. Rock outcrops and trees can be trigger points. Use caution in this terrain, especially if the surface snow starts getting moist. No new natural avalanches have been observed in the last 4 days along the highway corridor.

Confidence

Due to the number of field observations

Problems

Persistent Slabs

A weak layer is buried down 50 to 110 cm. Use caution on smooth, planar slopes. Riders could trigger this weak layer, especially from shallow snowpack areas. A large consequence avalanche is likely if triggered.

Dig down to find and test weak layers before committing to a line.Avoid convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

Wind affect has been observed at higher elevations, and wind transport was visible yesterday off the ridge tops.

Be cautious as you transition into wind affected terrain.Assess start zones carefully and use safe travel techniques.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Nov 24th, 2013 8:00AM