Regional Conditions for Southern Madison

A snowmobiler was side-hilling a slope in Sunlight Basin and triggered an avalanche. The rider was not caught or injured. Photo: R. Deleers

A natural avalanche on Ernie Miller Ridge failed on deeply buried facets earlier in the week on an east aspect. Skiers continue to report loud whumphs in the area. Photo: R. Wofford

A snowmobiler triggered this avalanche on a wind-loaded slope in Tepee Basin on Tuesday, 1/19. No one was caught. Photo: Anon

A snowmobiler triggered this avalanche on a wind-loaded slope in Tepee Basin on Tuesday, 1/19. No one was caught. Photo: Anon

A snowmobiler triggered this avalanche on a wind-loaded slope in Tepee Basin on Tuesday, 1/19. No one was caught. Photo: Anon

Small, natural avalanche on a wind-loaded slope in Carrot Basin in the Taylor Fork. Photo: GNFAC

Small avalanche on the Sage Basin Ridgeline in the Taylor Fork. Photo: GNFAC

Natural avalanches on Lightning Ridge. There were 10 natural avalanches from Wednesday's snow and wind and event in the Taylor Fork. Photo: GNFAC

A pair of avalanches on Lightning Ridge. There were 10 natural avalanches from Wednesday's snow and wind and event in the Taylor Fork. Photo: GNFAC

Avalanche in Sunlight Basin. There were 10 natural avalanches from Wednesday's snow and wind and event in the Taylor Fork. Photo: GNFAC

Avalanche in Sunlight Basin. There were 10 natural avalanches from Wednesday's snow and wind and event in the Taylor Fork. Photo: GNFAC

We looked at the avalanche in Hyalite that was triggered on Saturday 1/9/21. The slope angle was 33-35 degrees. It broke 2-3’ deep on weak facets below a hard slab, 1000’ wide and the debris was 5-9’ deep. East aspect, 9,800’ elevation. Photo: GNFAC

Skiers triggered this avalanche on Flanders Mountain on 1/9/21. It was triggered out of the photo to the right on a seperate slope around the corner. It propagated over 1000' wide, and 2-4' deep. Photo: GNFAC

From email: "...I found a small piece of this mostly low angle slope to have avalanched, probably from a day or two ago, a handful of older tracks were near it. I measure most of this slope around 26-28 degrees... This is on the farthest south part of the top meadow. An epic amount of whumphs up there, I stopped counting after I got to 10 on my second switch back. Our best one knocked snow out of a tree 100’ away. It feels like remote triggering is a very real possibility. Skies were more overcast than expected. While it never went blue, the sun poked out a little in the afternoon. Cold temps, 0F in the AM, warmed to 24F in the PM. 5-6mm surface hoar everywhere,..." Photo: S. Jonas

From email: "...I found a small piece of this mostly low angle slope to have avalanched, probably from a day or two ago, a handful of older tracks were near it. I measure most of this slope around 26-28 degrees... This is on the farthest south part of the top meadow. An epic amount of whumphs up there, I stopped counting after I got to 10 on my second switch back. Our best one knocked snow out of a tree 100’ away. It feels like remote triggering is a very real possibility. Skies were more overcast than expected. While it never went blue, the sun poked out a little in the afternoon. Cold temps, 0F in the AM, warmed to 24F in the PM. 5-6mm surface hoar everywhere,..." Photo: S. Jonas

Skiers triggered this avalanche on Flanders Mountain on 1/9/21. It was triggered out of the photo to the right on a seperate slope around the corner. It propagated over 1000' wide, and looks to be 6' deep at deepest. Photo: A. Blackmer

We saw this relatively very large, full width avalanches that was triggered on January 7, 2021. It broke on weak, sugary snow below hard wind drifted snow and recent new snow.

We saw this relatively very large, full width avalanches that was triggered on January 7, 2021. It broke on weak, sugary snow below hard wind drifted snow and recent new snow. Photo: GNFAC

On 1/8/21 we saw this snowmobile triggered avalanches that occurred on January 7, 2021. It broke on weak, sugary snow below hard wind drifted snow and recent new snow. Photo: GNFAC

From obs: "Shooting cracks and collapsing on the entire ascent to the Cinnamon Creek Lookout. Remotely triggered a R2-D2.5 on descent. 2-3 foot crown. Slide path was on an East facing slope at 9000ft. Failed on the same persistent weak layer being seen across most regions of the forecast zone."

One of many avalanches on the Sage Basin Ridgeline. These were on east through northeast facing slopes at 9300' elevation. The avalanches failed on the weak facets near the ground. Photo: GNFAC

One of many avalanches on the Sage Basin Ridgeline. These were on east through northeast facing slopes at 9300' elevation. The avalanches failed on the weak facets near the ground. Photo: GNFAC

One of many avalanches on the Sage Basin Ridgeline. These were on east through northeast facing slopes at 9300' elevation. The avalanches failed on the weak facets near the ground. Photo: GNFAC

One of many avalanches on the Sage Basin Ridgeline. These were on east through northeast facing slopes at 9300' elevation. They avalanches failed on the weak facets near the ground. Photo: GNFAC

We triggered numerous collapses or "whumphs" in the Taylor Fork. Some had associated shooting cracks that propagated up to 20 feet from the point of initiation. Photo: GNFAC

We observed two natural avalanches that likely failed 2-3 days ago in the Sunlight Basin in the Taylor Fork. They broke ~150-250 feet wide and ran 250 vertical feet. Photo: GNFAC

We observed two natural avalanches that likely failed 2-3 days ago in the Sunlight Basin in the Taylor Fork. They broke ~150-250 feet wide and ran 250 vertical feet. Photo: GNFAC

A skier kicked off a larger than expected cornice as they skinned up the ridge on the W side of Beehive basin on Sunday (12/20/20).

Recent small snowmobile triggered slides along the Big Sky trail in the Cabin Creek area. Photo taken 12/18/20.

Photo: J. Norlander

Small slides on road cuts along the Big Sky trail triggered by the groomer on Thursday night (12/17/20).

Photo: M. Global

Doug intentionally triggered this wind-loaded sidehill. Weak, faceted snow broke under a 1' deep soft slab of windblown snow. Small avalanches like this are indicators of instability on bigger slopes. These conditions can be found throughout the southern Gallatin, southern Madison, Lionhead and Centennial Ranges. Photo: GNFAC

We put up the Taylor Fork Weather station today. It measures wind direction and speed, RH, and temperature. Coupled with the Carrot Basin SNOTEL, this gives us a good idea on what is occurring in this range. Photo GNFAC

Light wind created soft drifts of new, low density snow near the ridgeline in the Bridger Range. This wind slab easily cracked when touched with skis, 20 feet along the ridge and 5-10 feet down, but didn't slide. This is a sign drifts will be unstable as they grow with more snow and wind. Photo: GNFAC

From IG post: "Weak and thin snowpack. A little sluff was all it took to entrain the whole season’s snowpack. S. Madison ~9000’ east facing" Photo: @vt.to.mt

From IG post: "Weak and thin snowpack. A little sluff was all it took to entrain the whole season’s snowpack. S. Madison ~9000’ east facing" Photo: @vt.to.mt

Large surface hoar crystals growing in the Upper Taylor Fork drainage on 12/9/20. 

Photo: E. Birkeland

The Gallatin Valley Snowmobile Association put up the beacon checker at the Sage Creek parking lot which leads to Taylor Fork. Thanks GVSA! Photo: GVSA

From obs: "Yesterday my partner and I attempted to ski the notch couloir off Koch Peak in the Hilgards. There was a strong western wind that picked up throughout the day, but we didn't notice any recent avalanche activity from the new snow. The snow seemed very consolidated underneath the new 6" or so that had fallen, but once we started skinning up the apron we noticed significant and variable wind-loading, so we dug a pit. Our pit was at the base of the couloir at approximately 10,400 and was directly east-facing. Here is a summary of our pit results: 25cm of large sugary facets at the ground (fist), 5cm ice crust on top of these facets (pencil), a 30cm very consolidated and well bonded layer (1 finger), a 1-2 cm light surface hoar layer, and a 5cm wind-crust ontop of that. We were worried about the deeper, consolidated layer that was sitting on top of the sugary facets propagating so we performed an ECT test and it failed on ETCP-17 on that layer with a Q3 sheer." Photo: L. Ippolito

Watch the video HERE!