We skied a lovely couple of laps of mellow-low angle powder off of Ghoulies today. We noticed no signs of instability while enjoying laps on a SE aspect above 6k'. The weather was calm, with light southerly winds and even a couple of spots of sunshine.
Before heading back in-bounds, we dug a quick pit to take a look at/for the surface hoar layer discussed recently in the Southern Whitefish Range. We dug at 6600' on a protected 37 degree, N slope, ~50' below the ridgeline, and had a total height of snow of 120cm. We found .5mm-3mm buried surface hoar below a 65cm soft slab of recent fallen and wind-deposited snow. Our ECT results (ETCX x2) didn't align with our expectations of the weak layer, while it proved reactive in our CT results (CTM12 & CTE10)... So we cut in a PST to bolster our opinions which resulted in PST 20/100 (End), confirming the potential weakness of the layer. The soft slab overlying the surface hoar had yet to tip the balance in that particular location, yet with a trigger in the right thin spot or additional loading with the incoming storms, it seems that this layer could easily be reawakened.
We did not ski the north aspect today and will keep a cautious eye on the evolution of the surface hoar problem as its further weighted through the next couple of storms. Fortunately, there is plenty of alternative terrain to be enjoyed in locations not harboring buried surface hoar!
