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Crown of avalanche that was remote triggered by a skier on 2/26/22. Photo: M. Cohen

Toe of debris from an avalanche triggered by skiers in the N. Bridger Range on 2/26/22. Photo: M. Cohen

From obs 2/26/22: "We were stopped on a flat bench on top of a steep rollover... when we heard a whumpf, and then a hard wind slab released on the slope below us and ran into the trees below. We then decided to enter the avalanche at the bottom of the debris to look at the crown, where we observed that the slab was about 60cm deep at its deepest, and ran around 50 feet wide, wrapping across a small aspect change. We did two ECT tests and observed propagation on the layer during isolation in both tests... We identified a P hard wind slab overlaying a 3 cm deep layer of 1F hard facets.

From obs 2/26/22: "We were stopped on a flat bench on top of a steep rollover... when we heard a whumpf, and then a hard wind slab released on the slope below us and ran into the trees below. We then decided to enter the avalanche at the bottom of the debris to look at the crown, where we observed that the slab was about 60cm deep at its deepest, and ran around 50 feet wide, wrapping across a small aspect change. We did two ECT tests and observed propagation on the layer during isolation in both tests... We identified a P hard wind slab overlaying a 3 cm deep layer of 1F hard facets.

Hey guys wanted to report a few avalanches we set off in the northern bridger range today, while skiing off of Seitz Peak. We skied the couloir (on horrible wind-scoured snow) without incident, then skied out onto the fan. I got a dozen or so turns in when the slope propagated 200’ below me, roughly 400’ wide. I skied off to the side to let it pass and watched it break sympathetically 200’ above my original trigger point, 12-18” thick at the thickest point. Overall 600’ wide, 8-18” thick, and ran over 1000 vertical feet. On our way down out of the bowl both my partner and I were able to break off more slabs through remote triggers, 50-100’ away getting them to break 8-12” deep and 100-200’ wide. All the slides broke on a layer of small grain facets in the new snow/old snow interface. We bailed on our other objectives for the day and skinned back out to the sled. Very touchy out there today! 

At around 11 AM, my partner and I observed a small, wind slab avalanche crown and debris on a Northeast aspect north of Frazier Basin (Image 1). Prior to seeing that avalanche, we had determined that wind slabs would be our greatest concern of the day, and we had tried to intentionally trigger any wind slabs on small rollovers in controlled terrain. We did not observe any signs of instability prior to seeing this small avalanche. We were stopped on a flat bench on top of a steep rollover talking about how recent we thought the avalanche was when we heard a whumpf, and then a hard wind slab released on the slope below us and ran into the trees below (Image 2). We then decided to enter the avalanche at the bottom of the debris to look at the crown, where we observed that the slab was about 60cm deep at its deepest, and ran around 50 feet wide, wrapping across a small aspect change. We did two ECT tests and observed propagation on the layer during isolation in both tests (SnowPilot profile will be publicly available once SnowPilot is back up). We identified a P hard wind slab overlaying a 3 cm deep layer of 1F hard facets. The layer below the avalanche interface was F hard facets. After this result, we dialed back our ski plans for the day. 

We dug two pits near where Doug and Ian were on January 12th. There has been so little snow since then that one of their pit sites was still clearly visible 6-7 weeks later. We could use some snow! The story here is very similar to that in the ranges from West Yellowstone through Big Sky. The top foot of the snowpack is very weak and getting weaker but we are waiting for snow before anything outside of isolated areas becomes unstable. ECTXs in both pits. The lower snowpack is largely locked up for now with a thick layer of pencil hard snow (rounds) below the facets. 

The total snow depth is ~200 cm which is less than what Doug and Ian found over a month ago. 

Video Describing Conditions

Bottom line: Stable for now, but this will change dramatically with a decent snowstorm.