Snow Observations List

We rode from Taylor Fork through Cabin Creek on March 17. We saw a few recent slab avalanches that happened after the last snowfall, and some recent natural wet loose avalanches, and a cornice fall. Both (all) of these types of slides are possible for someone to trigger the next 2-3 days.

Melt freeze crust on sunny slopes was 1-1.5" thick with dry snow below. Softened on south-southwest slopes by midday to early afternoon. Shady slopes seemed to be staying dry up high. Skies were mostly clear with calm wind.

We rode to the Wilderness boundary near Astral Lake and skied a small loop through to Green Lake. We then rode across to Lulu and Daisy Passes to look for avalanches. We saw several wet loose slides on south faces. We saw no new deep slab avalanches since Alex was there last week. After a late start due to some sled issues, we dug one pit looking for new upper level weak layers. ECTNs on hardness changes. We did not note any new persistent weak layers. 
 

While it remains possible to trigger very large avalanches on persistent weak layers near the base of the snow pack, it is clearly becoming less likely. Unfortunately, if you triggered one, it would be no less deadly. 

Had a pretty interesting collapse this afternoon while touring up the east ridge of Beehive. The slope I was on I measured at 30° at the highest, was below treeline but in a small meadow. The surface had melted and refroze. As I was touring across the small slope stomping to the to break the surface to set a better skin track the whole piece broke (150' wide by 50' down) together and moved down slope about 6". I quickly dug a little bit where it broke from the rest of the slope and it seamed to break near the ground, ~ 50cm and with the naked eye I could see large depth hore crystals and little to no rounding.

While I do think it was simply a collapse I was very surprised this happened and the way this whole piece moved on such a low angle slope. I hadn't seen something like this before. Guess it lines up with just how weird this season has been. 

~8560' west facing

45.31868, -111.38395

We were skinning in the valley to the East of Woody Ridge near the North end and observed a wet slide occur naturally due to a point release, moving about 500 ft downslope. While that was occurring it remotely triggered a dry slab avalanche approx. 50-100 ft adjacent on the same slope and elevation. The crown appeared to be 3 ft deep, possibly thicker, but we were viewing from afar so hard to tell. 9500 ft elevation, East aspect. 12:02 PM March 17, 2024. Air temp approx. 30F clear skies all day. 

Just got out from a hot few days at the Woody Creek Cabin. A highlight of the trip was watching a natural avalanche come off the unsupported northly end of the Climax slide path on Sunday the 17th. We believe it was remotely triggered by a wet loose point release which occurred a second before and ran immediately adjacent to the slab avalanche (see photo). Our best estimate for size is R2-D2, approximately 1.5m deep, and based on Google Earth measurements 75-100m wide, running about 200m. This occurred just before noon as the path received direct sunlight.

We also saw numerous roller balls and D1-1.5 loose wet avalanches in the Climax Path. The largest of which ran about 250 m, likely a D1.5 as it didn't have the mass for a D2 despite the distance.

We travelled in the trees on the east side of the valley, and gave run-outs a large berth. We skied moist snow on south aspects in Olie's Woods. 

Days old (?) crown on E aspect of Woody Ridge, about 9800'

Rode into The Throne via Battle Ridge on Sun. Trail in is heavily bumped and dirt starting to show. Guessing it will be about finished by the end of the week with the higher temperatures.      Skied a couple of laps on The Throne. Top layer was soft/slushy, or corn like, but the rest of the snowpack was one finger hardness until the bottom 10". Bottom of the snowpack remains rotten.    We saw two small point releases that were maybe 15' wide, caused by warming. Otherwise the snowpack felt stable in our area. 

Traveled N to a subridge of Naya Nuki and found similar results. No recent avalanche activity noted. 

We skied into Frazier Basin from the Fairy Lake road. On north facing slopes the snow was dry. On south facing slopes there was a 1-2" melt freeze crust which was softening on southeast-south facing slopes around 11am-noon. Snow was generally dry below that crust, probably got a little more wet today than yesterday.

We saw a few natural wet loose avalanches run throughout the middle of the day in sunny, steep rocky terrain. There were at least 4 old, deeper avalanche crowns, most of which had been reported and occurred 1-2 weeks ago.

We dug a snowpit on a north facing slope at 8,300'. Snow depth was 140cm and there was weak depth hoar (4F hardness) 30-40cm above the ground, below a 2-3 foot deep hard slab. Compression tests broke on the depth hoar/facets at CT29 and CT(30+1), sudden collapse/Q1. 

Skies were partly cloudy in the morning and cleared with scattered clouds through the day. Wind was calm.

Avalanche broke about 400ft wide and slid for 250 ft. 4-2ft deep at the crown

Snow was dry on North aspects when we got there around 10, and we started seeing a couple of wet loose on solar aspects where the terrain was steeper and rocky at 1130.

Snowpack started getting damp on the surface where we were skiing in the love chutes above Ainger Lake around 1300, on the descent back to the shaft house trailhead we were getting small roller balls and the snowpack was saturated below 6600 by 1430. 

saw this massive slide that spanned between the "Fat Maid" peak and all the way across Arden from the summit of Palace Butte yesterday.

Toured on the east ridge of Divide Peak this morning. From the summit, we saw at least three, if not more, large slab avalanche crowns and debris in Divide Cirque and surrounding basins. There were also a handful of visible wet loose slides and point-releases in the area. Winds were blowing out of the north but only really felt at ridge tops. Otherwise, it was incredibly warm. A bit after noon, the upper 6-8 inches of snow surface on the east shoulder had been impacted by the sun and wanted to slide on an old melt freeze crust below the surface. 
 

It was so beautiful up there today but the sun was powerful! The trail up and the basin were heavily impacted with the high temperatures and low wind. 

Toured up north of the ski area today. East and North facing slopes stayed cold, we experienced very light downslope winds below ridgeline, we observed little no windslab formation. Dug on a north aspect about 150' below the ridgeline. HS 150cm, ECTX, structure looked better than I thought it would, basal depth hoar was 1F-, but we got PST 65/145 and PST 40/145 to end up 20cm from the ground.

Thanks!

Localized observation for the Grotto Falls trailhead and G1 climbing area. An inch of graupel on the surface that probably fell in the late afternoon? I don't know how widespread it is, but very prominent in this area.

Toured up to the ridge between Beehive and Middle Basins with an AIARE L2. On the lower ridge we found:

• Pit 1
  • W aspect, 9045ft
  • Height of Snow 120cm
  • ECTP 26 in facets around 80 cm down
  • PST 38/100 end
• Pit 2 and 3
  • E aspect, 9023ft
  • Height of Snow 150cm
  • ECTP X x2
  • PST 40/100 end
  • PST 89/100 end

Skied up around Frazier Basin today, found limited instability in the new snow beyond sluffing. Wind loading was minimal with no large drifts, and no cracking in the new snow.  Underneath the new snow was a very supportive crust on all aspects. Did not see any new avalanche activity, but we did see numerous large old slides. Did see a good amount warming on solar aspects until the clouds moved in around noon or 11. 
 

On the morning on 3/14/24, a skier remotely triggered the Lawn Mower and an adjacent path on "Town Hill" in the Absaroka Range (outside of the GNFAC advisory area) while ascending on the other side of the ridgeline from the paths. The slide ran at least 1000 ft vertical.

From IG: "1/4 to 1/2 mile wide crown. Lawnmower and adjacent gully. 2-4 ft deep. Remote trigger from ~200 ft away. Crown is 8800 ft N/NW"

On our hike in we saw a crown above the East meadows on Ross. After getting up onto the shoulder we saw that the crown had a couple of inches of fresh snow on top of the debris so we assumed that the slide had happened 2 days previously with a possible human trigger. Could not see the full size of the crown due to not wanting to enter the terrain but my guess would be 2ft deep and a few hundred feet wide breaking above The Peel to the North of the Banana.

Just finished a weeklong ski from west Yellowstone to bear canyon, and thought I’d chime in that I didn’t observe anything that hasn’t been reported on already. I saw lots of deep slabs breaking near the ground, primarily on the north half of the compass. But sometimes not! There did not seem to be much activity in the newer snow, which was encouraging. In 110 miles of skiing I got a grand total of two collapses, which is close to an inverse ratio of what I experienced Nordic skiing near west Yellowstone earlier this year. It was interesting to see that despite the lack of snow, some avalanches were running almost full track. It seems like after a week of being on the snow I would see some sort of pattern, but I feel like I ended the trip with the same amount of confidence I entered it with, and didn’t feel comfortable exposing myself to hardly anything. 
 

I attached a couple photos of a slide I saw toward the head end of Swam Creek. The crown was 2-5’ deep and ~2000’ wide, and it stopped within 50’ of old growth timber.