Snowfall during the week before Thanksgiving doubled the snowpack. Weak snow near the ground can not surpport this heavy load and produced avalanches. Photo: GNFAC
14-15
From an email:
"A party of 5 of us went touring in the Bell Lake area yesterday (Sunday, 11/23/14). We skinned up into the cirque and were working our way up to a place where we planned to dig a pit when one member of our party remotely triggered a slide that propagated around the bowl...There were two different layers that slid, the top one was about 8 inches and was primarily new snow over facets. The bottom layer was about 3 inches and was a wind slab sitting on facets right on the ground. Nobody in our party was caught in the slide."
Forecast link: GNFAC Avalanche Advisory for Wed Nov 26, 2014
GNFAC Avalanche Advisory for Mon Nov 24, 2014
A skier triggered avalanche last Wednesday near Hardscrabble Peak in the Bridger Range (video) and cracking and collapsing of the snow in many ranges over the weekend illustrate a common problem: a poor snow structure (photo). The cold snap a couple weeks ago changed the snow on the ground into crunchy facets. Facets are weak and do not bond well to each other. They feel like sugar and you cannot make snowman out of them.
The thin snowpack is weak, but not unstable in areas without wind deposits. More snow later in the week may spike the avalanche danger. Photo: GNFAC
Forecast link: GNFAC Avalanche Advisory for Mon Nov 24, 2014
The snowpack around Lionhead (8,000') was only 43 cm deep. It was faceted with the larger crystals at the ground. I got no collapsing or cracking as I skied around. Once more snow falls I expect the snowpack to quickly become unstable. Photo: GNFAC
Forecast link: GNFAC Avalanche Advisory for Mon Nov 24, 2014
Before this storm there was a little over two feet of snow on the ground. A layer of facets below the ice crust and newly formed surface hoar are our likely concerns in regards to weak layers. With another foot added in the last 36 hours these layers may be unstable in areas of wind deposition. Photo: B. Fredlund