This is my first post on NWAC, it's only my second season splitboarding, and although I managed to get quite a few days in the backcountry last season, I was out with my fiance, who hasn't had any formal avy training yet and was on a very new AT setup, which she'd only taken out a few times on Rainier during the spring. It was also, only our second day in the backcountry this fall, so we were taking things really slow, and using the trip as more of a trial run and an excuse to dig a snow pit, exam the snowpack and learn. Since, I haven't dug a proper pit since level 1 last December, I apologize if any of our observations aren't super accurate, or my AIARE handbook scribbles are hard to read - my fingers were pretty cold and it's hard to write even with super thin touring gloves on :-).
That said, we decided to tour up to the Skyline cell tower above the lake yesterday, and I noticed that most of the lower elevation snow below maybe 4800' had a hard crust on the surface, which was very evident while riding down the front side, as it was mostly cut up and felt like chicken heads. I imagine this was probably due to all the sun on Saturday. However, when we got to the top the snow was still soft and powdery.
We decided to dig a pit on an untracked concave pillow above a run, which I believe the locals call "Stormies." But, we didn’t ride/ski it because the fiance wasn't ready, we weren't sure there would be enough snow cover further down and we didn't wanna have to skin back up if it was no good, as there was no clear skin track, and we were already pretty worked from digging the pit.
Anyway, we dug the pit all the way to the ground which was 160-180cm deep. That definitely seems like a lot of snow for this early in the season. Last year we found 160cm of snow in our level 1 pit up near Grace Lakes, but that was around December 22nd. In any case, there were no fractures on the CT or ECT even though there was a rain crust layer about 100cm up from the ground that looked like it could be weak or cause instabilities above or below it. I imagine this is the same 11/16 rain crust layer I saw in the photo from the rock mountain pit. We didn't do a separate shear test, but I pulled on both the CT and ECT columns after we'd done our tests and they needed a lot of force to get them to shear, and even when they did move the fracture was uneven and seemed to happen further above the rain crust than I would expect. My hopes are this is a good sign of stability moving forward.
However, as I mentioned above, we did see a natural avalanche on a S/SE slope while leaving Stevens, and it looked like it might be about the same depth as the crust we saw above "Stormies." So, perhaps that layer could be more reactive and problematic on the more S/SE aspects, which I imagine is something to keep in mind even if other aspects sinter down.