Avalanche Forecast
Issued: Jan 25th, 2017 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs.
grant statham,
Avalanche Canada
Moderate danger ratings do not tell the whole story. The snowpack is weak, and isolated avalanches can be triggered. Be extremely careful around any avalanche starting zones. 10mm surface hoar is growing on the snow surface . . . our next weak layer.
Summary
Weather Forecast
There is no new snow in the near-term weather forecast, as a ridge of high pressure remains stationary over the central rockies. Some cloud cover may appear, but no precipitation is expected and temperatures on Thursday will range from -5 to -10 and light NW winds.
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
One new avalanche (last 24-hr) was observed at 2600m on the SW side of Mt. Ogden, but we could not tell how deep the fracture line was. 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.
Confidence
Problems
Persistent Slabs
The mid and lower snowpack is weak, with both facets and surface hoar buried and producing shears. The tipping point is whether or not there is a cohesive slab overlying these layers. Pay close attention to the slab properties in the upper snowpack.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 26th, 2017 4:00PM
