Avalanches failing on the ground can be triggered by recreationalists this weekend on approach slopes to ice climbs, between pitches, or on slopes that look inviting to ski.
Early Season Conditions persist.
Wind slabs up to size 2 can be expected in the alpine and exposed tree-line locations. These slabs may step down to the persistent layer of basal facets and/ or a melt/freeze crust.
In the past 2 days, several avalanches have ran on a crust and/or the ground. The crust component is most noted in the Lake Louise region on slopes that had snow in late October. Slopes attractive to skiing are suspect and climbers carefully consider approach slopes and ledges between pitches.
In the past 48 hrs, several natural avalanches to size 2.5 failing to ground were reported by both Sunshine and Lake Louise ski hill's. On Friday, several avalanches were triggered by ski cuts or explosives. Lots of whumphing and shooting cracks was reported with one slope triggered from 10 m away which then propagated 60-70 m wide.
While we have limited observations, ski hills are reporting slabs that are very sensitive to human and natural triggers.
It's still very much early season. With 30-50 cm at tree line and 50-80 cm in the alpine. Many early season hazards LURK below the snow's surface.
Wind & persistent slabs at tree line and in the alpine have been sensitive to human triggering and also failed naturally. Once triggered, failures have stepped to ground running on facets/intermittent early season melt freeze crust.
Forecasters are still working with limited observations.
On Saturday, temperatures will again be mild. Freezing levels are forecasted to climb to 2100 m for slopes furthest East of the Divide. Winds will be moderate SW and skies will be a mix of sun and cloud.
For more info, please see the Mountain Weather Forecast.
