Glacier Creek, Purcell Mountains
We skied the East Cauldron Glacier up the South Fork of Glacier Creek in the Western Purcell Mountains yesterday November 11, 2018. We had mostly clear skies, calm winds and temperatures ranging from -1C to -15C. We were able to drive up to KM 34 (1550m) with high clearance 4 X 4 on the Glacier creek forest service road. This made our day significantly longer as it added 9km of logging road travel each way.
We traveled on skis between 1550m and 2750m primarily on north facing terrain. There was about 35cm of snow at 1550m (parking area), 60cm at 1800m (end of road), 90cm at 2200m (treeline) and upwards of 160cm on glaciated terrain above 2450m. There was not enough snow to safely linked turns below 2000m where plenty of barely covered early season hazards exist. Above that elevation, skiing was excellent. The top 15-25cm was evenly distributed low-density powder snow. This overlie a denser supportive multi layered snowpack. Traveling conditions were surprisingly fast.
We saw a few old avalanches from last week’s cycle. In total, we saw 3 size 2-2.5 slab avalanches out of very steep terrain (rocky, lee & planar) on north aspects with start zones between 2500m to 2300m. Crowns looked deep and in the 100cm range. Two of these avalanches appear to have been triggered by large loads like a cornice or an ice-fall. The weak layer of these avalanches is unknown, we suspect the Oct 26th interface.
We did a few test profiles to build our early season confidence. At 2200m we noted a hard sudden shear 70cm down from the surface in a soft facet layer below a crust. At 2450m, we had a few moderate resistant shears in the top 50cm and a moderate uneven sudden collapse down 120cm in a soft facet layer below a crust. We suspect that the later shear is the Oct 26th interface.
We didn’t see/feel any signs of instability. Our main concerns were early season hazards below treeline, newly covered crevasses on the glacier and steeper unsupported terrain above treeline. All in all, it was a great first day out to investigate early season conditions with friends.
Enjoy the transition into winter!
ACMG Mountain Guide