Spent the last seven days, Jan 20 – 27, ski touring at Powder Creek Lodge in the Purcell range near Kaslo BC.
The first six days of the tour were clear cold and calm, overnight low temps –20 degrees, daily highs –8. Previous NE winds had created widespread, variably distributed surface slab development in open areas from below treeline to the alpine. We had best luck with ski quality on north and west slopes treeline and below. The alpine zone was super variable ski quality.
Snowpack and Avalanches: The cold temps made for good facetted powder where not wind affected.
The windslabs, which ranged from soft (4F) to hard (P), 5 – 30cm thick, settled and bonded well as the week progressed, giving a couple very small results with ski cutting. No significant cracking, propogating, or whumphing. The early December crust is buried down 130cm at 1900m, hard to no results in snowpack tests. The crust does not exist above this elevation in the Powder creek tenure, though the interface from this date is discernible as a layer of rounding facets. One natural sz 2.5 avalanche occurred mid week on this layer, over a metre deep and 200m wide, on a steep sunny SW facing bowl at 2100m. On Jan 25 there was a sz 2 natural 50cm crown, out of a steep chute, also on a solar aspect at 2100m.
With this snowpack and stable weather we were able to gain confidence throughout the week, attaining some great alpine ski touring objectives with a thought to minimizing our exposure to over head cornice hazard, solar slopes in the PM, and really rowdy unsupported terrain.
The thing now is that last night we received 20cm of low density snow, and more snow is forecast. This sits on a surface hoar layer that formed this week, all aspects and elevations, average size 5mm. The SH sits on a suncrust on steep south slopes.
This newly buried layer is sure to be a concern when the fresh snow on top settles out and densifies, or the wind creates slab conditions.
This synopsis will apply to the greater Kootenay Boundary region as the weather patterns have been similar over the area.
Joel McBurney, SG
Nelson BC