Snow Observations List

Snowboarder triggered this slide on a rollover on East Republic. Reportedly ran 80' wide, 1-1.5' deep. No one was caught.

There was 4 inches of new snow in Taylor Fork, and there was wind drifting in several places. We rode to the wilderness boundary to dig a pit. We were on a south aspect at 8,800’. HS 125cm (~4 feet), ECTN5 on surface hoar under the new snow, ECTN21 on facets 1.5 feet below the surface, ECTN 28 on facets near the ground. We rode past the Otter Slide to dig on a north facing aspect, and we had an ECTP5 on buried surface hoar. There was 6” of new snow on top of the surface hoar layer that propagated. While leaving Taylor Fork this afternoon it was beginning to snow. The additional snow in the forecast will likely make this surface hoar layer more reactive now that it is buried. Additionally, the poor structure throughout Taylor Fork could make the deeper weak layers more reactive.

We exited Bridger Bowl via the ridge and dug a pit at the top of Lazy Susan near The Ramp. It was 111 cm deep and full of facets. The lower half was facets, and the top was faceting, and there was surface hoar. We had ECTN17 and 18 at 79cm. Felt weak, but generally stable. You could trigger an avalanche somewhere, but danger is decreasing without new snow and wind-loading.

Snowmobiled to 8200ft then skied up to 9000ft. Dug a snow profile to ground on NE aspect at 8800ft. Height of Snow was 120cm (4 feet). Multiple weak layers in the snowpack including one about a foot down and a thicker layer of faceted sugary snow in the bottom 2 feet of the snowpack near the ground. ECTN29 on a crust and small grained facets about a foot down from the surface, however that slab layer released when a shovel was put behind it with a sudden pop and very little friction, see grainy photo. Surface was faceting old powder which could be another weak layer when buried. Not very reactive in this spot at the moment likely due to lack of new snow in a while. However generally poor snowpack structure is not reassuring and will need to watch when this snowpack gets rapidly loaded by new snow or wind blown snow. 

Observed recent small wind slab avalanches under the ridgeline as well as one larger slide that broke on weak snow near the ground, likely cause by cornice fall. 

@ 7740' east south east aspect 20 deg slope we found HS 87-105cm, large grain faceted snow near the ground, ECTN 29 @ 55cm above Xmas crust. Saw multiple D1-D2 DL or unknown ( couldn't see crown) in ramp/ wolverine/ hourglass couloir. 

Skier unintentionally triggered and was caught in wind slab avalanche on the Y couloir in Sheep Creek Drainage. Skier was carried 10m before self arresting. The slide ran ~250m down and broke across the entire width of the couloir. There were no injuries and skied away. 

Yesterday we tested and skied a well-protected, NE-facing line above Blackmore Lake. There were strong winds during our approach and we observed evidence of wind loading on northern aspects. By around 2 pm, wind speed and wind loading reduced significantly. At our pit location, we observed a thin wind crust (1-2cm) that moved quite readily. This layer did not move during stability tests and did not propagate while skiing, but released readily while skiing. At the bottom layer of the snowpack, we noted that the grain size increased since our visit to the area last weekend, and the faceting in this layer was much more apparent particularly at the bottom of the layer (see photo). 

I am finding very solid snowpack in most areas. We dug one pit yesterday that exhibited two weak layers in the top 35cm and one near the ground. This was a wind loaded slope with HN 230cm. CT test did not fail. No evidence of surface hoar at this location. 9100 feet on a NE aspect.
At lower elevations I found evidence of surface hoar forming, but not necessarily on the snow, see photo.

We are entering a warming trend, which is generally healthy for the snowpack. The conditions are right for surface hoar development; however, I am only finding very isolated evidence of this. Something to keep an eye out for.

We have several weak layers in the snowpack that could fail causing an avalanche, likely a large deadly avalanche. It's hard to find places that exhibit reactive test results, but the evidence is in recently human triggered avalanches. We are not getting a ton of new snow and together with the mild temperatures this will create a strong snowpack over time. The places to watch out for are shallower snowpack areas where the persistent weak layer is easier to trigger.  

From IG 1/7/23: We dug a pit in island park back up Blue Creek on the Centennials side. South facing slope. ECTX

Toured into Hyalite basin and found evidence of what looked like an older and large slide on Hyalite peak. Intense wind scouring appears to have taken place, or the slide ripped to the ground. Ample evidence of wind loading and stripping throughout the bowl left us with enough evidence to turn around without digging. We skied lower angle trees out of the basin and then toured into Divide basin. We dug a pit on the sheltered shoulder of the typical skin track to divide peak and got an ECTx. Snowpack was well bonded and congruent to the ground on this specific E-NE aspect and slope Snowpack was about 100-145cm deep in total.

We toured into Beehive Basin for our level 1 class.  Widespread surface hoar up to 6 mm on west to south aspects (we did not tour on any other aspects).  Buried SH under the recent 7 cm of storm snow was present, though it was not fully preserved. Some feathers were still vertical while others were knocked down. Buried SH was reactive but not propagating long distances. Small, short cracks were observed on that layer in our tour. Wind-loaded pillows from prior loading were visible on much of the steeper western aspects off of the ridge, especially down low and in cross-loaded gullies. 

Overall, we were happy with the snowpack structure in our singular pit location, surface hoar not withstanding (see attached profile).  Snowpack was right side up and the basal facets were moist, beginning to round, and pencil hard. The ground was warm and soft (and a bit muddy) with a stout 2 cm plus ice layer. 

On the lower angle wiggles in the basin, the ski quality was quite good, and the powder was quite loud. 

Dug a hasty pit on E facing 23 degree slope at 8100 ft above Sportsman Lake. Overall snow depth 165 cm. Found all the familiar suspects including depth hoar, the Thanksgiving weak layer and two 1F layers between 4F layers in the top 60 cm of the snowpack. CT and ECT both produced no results. Temps were warmer in the valley, but didn't show signs of being above freezing above 7500ft.

We skied mellow terrain anyway and made very sporty turns on our nordic skis.

From IG 1/7/23: "Natural slide in avalanche bowl up in fairy lake today."

Location: 45.165, -111.35808 (onX) 

Elevation: ~9,200 feet

While riding a small NNE facing slope near the trail on Buck Ridge, a snowboarder triggered and followed a cornice slide that propagated approximately 75 feet and slid about 20' vertical. The one rider was caught and carried approx. 10' and ended up buried upright, waist deep with no injuries. 

Dug a pit today near the prayer flags and got an ECTX on E slope around 9200’ HS 140cm. Facets near the ground appeared to be rounding and bonding nicely. There is a weak layer at 110cm but not a cohesive slab above it, could be interesting when we get new snow. Did observe newly formed facets on the surface. Minor wind transport at ridge line in the afternoon. Mostly right-side up, quality riding 

More pictures, video and information can be found HERE on our Incidents page.

At 1:30 PM on Jan 6th a large avalanche poured over the cliffs on Saddle Peak, outside the boundaries of Bridger Bowl. Clouds obscured the starting zone. Multiple groups were in the runout zone, including a skier hitting a jump. One person was caught and buried up to his neck. He was able extricate himself and was unharmed. He did a beacon search at the toe of the debris. He estimated the debris was at least six feet deep.

We believe this was a natural avalanche that broke in the new and wind drifted snow. Bridger Bowl measured 6" of new snow with 0.75 inches of Snow Water Equivalent at the Alpine Wx. Station. The avalanche was estimated to be 3 feet deep, and measured on Google Earth to be 550 feet wide and 2100 feet long. 

We rode into The Throne, and skinned up the ridge. While skinning we saw cracks in front of our skis in the 6” of new snow. The wind was gusting from the north most of the day–our skin track was filled in by the time we skied out. Where we dug, HS was 130 cm (~4 feet) on the NE aspect at 8,100 feet. ECTN 8 on the new snow, and ECTN 24 at a layer of graupel about 1 foot down from the surface. This layer was noted by skiers in Texas Meadows yesterday.

While skiing back to our sleds we triggered a small slide in a wind loaded pocket of snow on a ~35º, isolated terrain feature (SS-ASu-R1-D0.5). This was on a southerly aspect, at about 7,000 feet, 4-6” down on surface hoar, 15’ wide, 30’ vertical run.

While skiing around our boundaries I observed well developed surface hoar that was relatively widespread in undisturbed areas. The photo included seemed to go well with the fx. 

I came across this older avalanche yesterday when I was guiding a group in the Kirkwood area, it’s an area in the Cabin Creek drainage. It looked to be an older natural slide probably just after the last storm cycle a few days to almost a week ago now. After seeing the old slide and taking a look we found a safe slope with the same aspect approximately 300 yards away with the same NNE aspect, dug a pit and did an ECT test with stabile results.

Kirkwood

North, North East Aspect

Approximately 39 degree slope (Because of a creek with open water just below the slide, I couldn’t get close enough to accurately measure the slope)

ECTX…When digging the pit we could see what looked like 2 weak layers in the snow pack and a faceted layer at the ground. We had no failures during the test and even after the test when I pulled and pried with a shovel, the snow held together and showed signs of stability.