Avalanche Forecast

Issued: Dec 29th, 2018 4:00PM

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

snow safety, Parks Canada

Little Yoho.

An avalanche cycle is expected from this weekend's storm. Avalanches are expected to be touchy for a while. Avoid avalanche terrain. Field ice climbers should be aware of the potential for avalanches reaching full path.

Summary

Weather Forecast

Snow and wind has created overhead hazards in the Yoho region.

Snowpack Summary

In most of Little Yoho there is 60-80 cm of settled snow over top of the Dec10 surface hoar/facet layer. Shears on this layer are generally producing hard but sudden planar results. In shallow areas (lower elevations and Mt. Dennis) the main concern is the weak basal facets which continue to produce whumphing and easy test results.

Avalanche Summary

Avalanches have been reported but their size and extent are unknown.

Confidence

Problems

Persistent Slabs

This problem is a slab overlying the Dec 10 surface hoar/facet layer which is down 40-80 cm. Although this layer is gaining strength, there is still uncertainty with this interface. Evaluate this layer carefully prior to committing to bigger slopes.

Use caution on open slopes and convex rolls at treeline where buried surface hoar may be preserved.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Wind Slabs

Minimize overhead exposure during periods of heavy loading from new snow, wind.Use caution in lee areas. Recent wind loading has created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 2.5

Valid until: Dec 30th, 2018 4:00PM