Regional Conditions for Bridgers

Skiers triggered this avalanche on the north face of Mt. Blackmore on Sunday June 9th. Photo: C. Pruden

Skiers triggered this avalanche on the north face of Mt. Blackmore on Sunday June 9th. Photo: C. Pruden

Natural wet slabs were widespread on Fan Mtn. near Big Sky during the week of 5/13-5/16. Photo: E. Mullen

This natural wet slab slid early this week, Monday (5/13) or early Tuesday (5/14), near Beehive Peak. This photo was taken 0745 Tuesday morning. Photo: @cfirer

Debris from a wet slab that released naturally Tuesday evening on saddle Peak. Debris ran very far into the runout compared to similar sized dry slabs that often occur on this path. "South side of 1/4 Saddle slid sometime last night. Looks like cornice drop then step down to near ground. Hi yesterday at Alpine was 62." -R. Elliott/BBSP

This wet slab released naturally Tuesday evening on saddle Peak. "South side of 1/4 Saddle slid sometime last night. Looks like cornice drop then step down to near ground. Hi yesterday at Alpine was 62." -R. Elliott/BBSP

"South side of the Glide Plane released as a glide avalanche last evening (May 12th) sometime around 6 pm according to source. Bed surface was ground in starting zone of wet clay soil sparsely covered in long grass.  Debris chunks, some snowmobile sized, rode up on surface and slid approx. 200 vert.  Debris could have bumped a tower on the old Alpine lift if it still lived there. Last freeze was 6 am on the 10th of May.  The high temperature on the 12th was 59 degrees at 4 pm." Photo and observations: BBSP

Photo: BBSP

"South side of the Glide Plane released as a glide avalanche last evening (May 12th) sometime around 6 pm according to source. Bed surface was ground in starting zone of wet clay soil sparsely covered in long grass.  Debris chunks, some snowmobile sized, rode up on surface and slid approx. 200 vert.  Debris could have bumped a tower on the old Alpine lift if it still lived there. Last freeze was 6 am on the 10th of May.  The high temperature on the 12th was 59 degrees at 4 pm." Photo and observartions: BBSP

"South side of the Glide Plane released as a glide avalanche last evening (May 12th) sometime around 6 pm according to source. Bed surface was ground in starting zone of wet clay soil sparsely covered in long grass.  Debris chunks, some snowmobile sized, rode up on surface and slid approx. 200 vert.  Debris could have bumped a tower on the old Alpine lift if it still lived there. Last freeze was 6 am on the 10th of May.  The high temperature on the 12th was 59 degrees at 4 pm." Photo and observartions: BBSP

"South side of the Glide Plane released as a glide avalanche last evening (May 12th) sometime around 6 pm according to source. Bed surface was ground in starting zone of wet clay soil sparsely covered in long grass.  Debris chunks, some snowmobile sized, rode up on surface and slid approx. 200 vert.  Debris could have bumped a tower on the old Alpine lift if it still lived there. Last freeze was 6 am on the 10th of May.  The high temperature on the 12th was 59 degrees at 4 pm." Photo and observartions: BBSP

Skiers found fresh wind slabs that were easily triggered on Saturday 4/27 near Beehive Basin in the northern Madison Range. Photo: E. Birkeland

Skiers easily triggered loose snow avalanches of the 3-5” of new snow. This morning (4/27) on the Bridger Ridge. Photo: @smooneyski

Skiers easily triggered loose snow avalanches of the 3-5” of new snow. This morning (4/27) on the Bridger Ridge. Photo: @smooneyski

This crown was observed on 4/18/19 on a slope that previously had a glide crack. It probably broke during heavy rain on 4/7-4/8. Photo: GNFAC

This wet slab crown was observed on 4/18/19 on the west side of the Bridger Range, and it likely ran during heavy rain on 4/7-4/8. Photo: GNFAC

Link to donate to the Friends of GNFAC: https://www.givebiggv.org/organizations/friends-of-the-gallatin-national-forest-avalanche-center

This slide occurred around 1400hrs on 4/19/19 with sunshine and temps above 50 F. Photo: GNFAC

Activity from 4/19/19. Photo: GNFAC

Activity from 4/19/19. Photo: GNFAC

Activity from 4/19/19. Photo: GNFAC

Activity from 4/19/19. Photo: GNFAC

Wet loose slides ran naturally on 4/18 on northeast through south aspects in the Bridger range. Photo: GNFAC

Wet loose slides ran naturally on 4/18 on northeast through south aspects in the Bridger range. (Screenshot of BBowl webcam).

Photo: GNFAC

Photo: GNFAC

Photo: GNFAC

Skiers saw this crown on Saturday (4/13) in the N. Bridgers. Photo: M. Gaffney

Recent spring snow has created instabilities that are confined to within the new snow. Areas such as ridgelines where fresh drifts form should be approached with caution. Cornices and fresh wind slabs should be avoided after fresh snow and/or strong wind. Photo. M. Gaffney

Photo: GNFAC

From e-mail on 4/11/19: "We found reactive storm slabs and touchy windslabs near ridgelines. We kicked off a small windslab in 4th of July from the top of the couloir. Attached is a photo of the crown to give you a depth perspective. It was about 6 feet across and 3-4 inches deep."

Heavy rain on Monday produced a widespread wet loose avalanche cycle in the Bridger Range. Photo: GNFAC 

Snowpit dug at Bridger Bowl on Monday (4/8). Heavy snow and rain are creating dangerous avalanche conditions. Photo: BBSP

Below 3-5" of new snow there is a supportable frozen crust on top of a wet snowpack on most slopes. Avalanches are mostly confined to the new snow on top of this crust (wet loose, dry loose, wind slabs). However, where the snowpack did not freeze below the new snow, or when this crust melts, deeper wet slides are possible. Photo: GNFAC

A glide crack (the "frown" of dirt in the middle of the image) has opened up on the SE face of the Throne, in the Northern Bridger Range. Photo taken 4/1/2019.

Photo credit: GNFAC

Snowmobile-triggered slide near Fairy Lake on Saturday (3/30). New snow was drifted into small wind slabs that may remain reactive in isolated areas.  Photo: P. Cronin

Two pits on the west side of Saddle peak. They were dug relatively close to each other, but subtle changes in aspect and elevation resulted in very different conditions. North-facing slopes remain cold and dry for now, while anything that is in the sun is transitioning to a springtime snowpack. Photo: GNFAC

Skiers triggered this wet slab avalanche on Saturday afternoon (3/23). Warm sunny days have weakened the snowpack and made wet avalanches possible. Photo: G. Egnew

Skiers triggered this wet slab avalanche on Saturday afternoon (3/23). Warm sunny days have weakened the snowpack and made wet avalanches possible. Photo: G. Egnew

Debris pile from the smaller of two wet slab avalanches on the south-facing chutes off of Texas Meadows. P: A. Schauer