Avalanche Forecast

Issued: Jan 27th, 2017 4:00PM

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

Avalanche Canada tim haggarty, Avalanche Canada

Although natural activity has diminished and the danger levels have dropped to moderate, human triggered avalanches remain possible with this generally weak and variable snowpack.

Summary

Weather Forecast

The west winds that picked up this morning promise to bring a band of moist weather from the coast. Expect overcast skies with the potential for light precipitation and possibly strong winds with warmer temperatures Sunday. After this weather passes expect at return to clear skies and colder temperatures Monday.

Snowpack Summary

In the Emerald Lake Slide Path, a generally weak snowpack exists. At 2000 m, in a 135cm of snowpack, the Jan 17 surface hoar layer is down 25cm with sudden planar test results - but minimal slab formation above. In the mid-pack, the Dec facets are 20cm thick and prominent, and near the ground a layer of weak facets sits just below on old ice crust.

Avalanche Summary

Monday's avalanche control in Yoho Park produced numerous size 2 and 2.5 avalanches on Mt Dennis and one size 3 on Mt Bosworth. Minimal results in KNP control on Thursday see the BYK bulletin for details. A few natural avalanches have been observed over the last week but activity seems to have diminished in the last 2 days.

Confidence

Problems

Persistent Slabs

An icon showing Persistent Slabs

The mid and lower snowpack is weak with facets producing moderate to hard shears. In the upper snowpack around treeline a buried layer of surface hoar produces easy to moderate shears. Pay close attention to the slab properties overlying these layers

  • Use conservative route selection, choose moderate angled and supported terrain with low consequence.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 3

Valid until: Jan 28th, 2017 4:00PM