New snow + wind + terrain =
Heather and I spent the afternoon ski touring on the Western Rim of Moose at Kelly Canyon. Recent snow, about 20cm new since Monday night, and strong winds transported a lot of snow across the western end of Kelly Mountain, leaving a large wind slab at the top of the Jihad run. An easy ski cut mitigated the hazard. The crown measured 60cm (about 24″) and pulled out most of the new skiable slope at the start of the run.
click on the image to see it better
The recent snow is heavy and rests on top of lighter density snow which is often referred to as an “upside down” snowpack. This can create potentially dangerous surface instabilities, which showed itself near the bottom of the Big Easy. A ski turn started a point release sluff as i skied the 40 degree slope; picking up a fair amount of surface snow as it traveled down hill, chasing after me. This one may not have been big enough to completely bury me but i can imagine hitting those trees could have caused some bodily harm!
Our test pit showed 120cm of settled snow at 6,400′ on an Easterly aspect. The snowpack includes several buried persistent layers (mainly ice layers and melt/freeze crusts) with the most reactive layer (thin ice layer on top of melt/freeze layer) in our stability tests at approx 50cm in depth. Compression Test scores recorded as CT 11, Q1 @ 50cm (x 2) slope angle 35*. There is definitely a slab out there.
So, what does this mean to you? I know what it means to me. Surface instabilities are very sensitive to human triggers right now on certain aspects of Kelly Mountain AND there is reason to be concerned about deeper instabilities within the snowpack in that area. Don’t take our easily accessible low elevation terrain in the Western Big Hole Mtns for granted. Instabilities are lurking, and the possibility of harmful snow sluffs and avalanches are a real possibility.