Correlating stability tests to slope skiability
This last weekend, my girlfriend and I borrowed some sleds and rode out into the Mt Bachelor sidecountry, toward Tumalo mtn. We parked them at Todd lake, and climbed a small ridge on skins to get a few turns in, as we were on a tight schedule to meet up with our group of snowmachiners.
Halfway up the climb, I dug a pit and found about 14" of soft to very soft on top of a firm crust, with about 3" of soft below that. This was on about a 25-30 degree slope. The temps were in the high 20's F.
The snow felt very stable, and was not wind loaded at all. I did a compression test on about a 18" high column and was able to get it to break at the crust on the 8th tap from the elbow. The bed surface was about Q2 I guess...not super smooth, but not super rough. I cut out a mini Rutchblock (only about 18" deep) and was able to get it to break on the 3rd jump, once again at the crust.
I haven't been able to put much of my actual snow science to work in the last 2 years, and I've never been very clear on correlating stability tests with actual skiability of slopes. I had watched guys highmarking on sleds for the last 2 days on much steeper slopes, but I wanted to evaluate the actual upper snowpack a little more scientifically.
We mainly skied some lower angle stuff to be safe, but what guidelines does one use for determining max slope angle to ski based on the compression test results and the bed layer interface? What I saw as definitely not a NO-GO to me, but it was a signal to stay off steeper stuff, at least from an inexperienced point of view.
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