24-25
We saw a handful of avalanches above treeline terrain that seemed to be wind slabs. However wind and snow had obscured them and I suspect there had been a lot more.
In the last five days, this area has received snowfall containing 4.5-5.3 inches of water which has settled to about 3 feet of new snow.
Island Park
In the last five days, this area has received snowfall containing 4.5-5.3 inches of water which has settled to about 3 feet of new snow. Winds last sunday night from the southwest reached speeds up to 80 mph before easing, but then they blew from the north today.
We saw a handful of avalanches above treeline terrain that seemed to be wind slabs. However wind and snow had obscured them and I suspect there had been a lot more.
No cracking in the new snow and one possible collapse. Interestingly - My stability test scores had actually improved since Friday when there was less new snow. They broke and propagated just under a crust under the new snow. ECTP12's on Friday. ECTN & ECTP25 today. The reason is that they have been breaking on old, broken snowflakes....not facets.
Key points
- The new snow seemed mostly stable on sheltered slopes
- Wind loading is the main issue.
- With this kind of loading, it often finds weaknesses in the snowpack. I don't expect any moster slides, but also wouldn't be surprised to hear of one being triggered if tomorrow were a busy weekend day with lots of people out
- Avoid alpine terrain above treeline where winds have drifted lots of snow. Avoid hanging out in runout zones of big paths
The snow ranger crew was riding around the Bridgers today and we spotted this slide in the bowl to the south of Hardscrabble peak. It looked fairly recent (last 2 days) but a little hard to tell due to the new snow since yesterday and blowing snow today. Photo: USFS Snow Rangers
Forecast link: GNFAC Avalanche Forecast for Wed Mar 19, 2025GNFAC Avalanche Forecast for Thu Mar 20, 2025
As we neared the ridgeline and shifted to a more southerly aspect, we noted scalloped and scoured snow surfaces and the development of thin wind skins and a few 1-2" wind slabs. Photo: GNFAC
Cracking in wind drifted snow
Toured into Frazier basin today. Saw cracking in wind drifted snow near a ridge top at 8500’. The cracks were about 15 ft across. The drifted snow was about 1-1.5ft thick and still pretty soft. New snow depths varied, some areas were completely scoured.
Wind Drifted Snow in the Bridgers
After a weekend of stormy weather, dropping about 1 foot of snow (~1" of SWE) on the ground, we toured out to the Throne today to see how the new snow had settled and what the winds had done to it. As we approached the main face, we noted swirling winds transporting a fair amount of snow. Generally, winds blew out of the north with gusts from all sorts of directions throughout the day.
Despite the active snow transport, east facing snow surfaces were still soft with minimal to no slab development. We did not note any signs of instability as we traveled up the face. As we neared the ridgeline and shifted to a more southerly aspect, we noted scalloped and scoured snow surfaces and the development of thin wind skins and a few 1-2" wind slabs. We dug a snowpit on a southerly aspect at 8360' (HS: 212) and got an ECTP12 on an 18" wind slab. This test result, as well as the few small wind slabs we noted were the only signs of instability seen today. We chose to stay off of steep southerly terrain and traveled back to the main face where winds had minimally impacted snow surfaces.
On the ride out, we had great views of the Bridger Ridge and did not see any signs of new avalanches across this broad area.
Didn't see signs of instability in new snow at Ross Meadows
Toured up to the meadows below Ross Peak today. Didn't see much cracking within the new snow (mostly just directly under our skis). At around 8000' we found a foot of right side up snow above a crust. I dug a hand pit below the crust and didn't get any planar failure. On our way down we started to see the surface snow getting heavier as it warmed up.
We were in a fairly protected zone but saw a few small patches of soft wind slab and noticed snow being transported over the ridge above us when visibility was good.