Regional Conditions for Cooke City Area

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

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

"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

Spring Sled Fest is May 18th! DJ, Free BBQ, Raffle. All proceeds go to the Friends of the Avalanche Center. More event details here: https://www.facebook.com/events/2290792671007553/ Thanks to Mark Christensen @markass406 and Nick Donovan @skidooin_it for organizing the event.

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

Northwest aspect near 9,500’. Likely ran weekend of 4/20-4/21. Photo: GNFAC

This slab avalanche near Goose Lake outside of Cooke City appears to be a wet slab triggered by a wet loose slide. Warm temps and sunshine the past few days were the perfect recipe for wet snow avalanches. Photo: B. Fredlund 

Large natural avalanches were observed near Goose Lake outside of Cooke City. These slides are a reminder that unstable conditions still exist in upper elevation terrain. Photo: B. Fredlund 

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

Wet slabs were observed near Cooke City on 4/20/19. Riders reported multiple slides similar to this one. Photo: K. Taylor 

Observed 4/20/19. Crown estimated 3-5' deep. Above freezing temperatures, sunshine and rain created a wet and weak snowpack. Photo: G. Antonioli

Observed 4/20/19. Crown estimated 3-5' deep. Above freezing temperatures, sunshine and rain created a wet and weak snowpack. Photo: G. Antonioli

Natural wet slab avalanche on Wall Mtn. near Cooke City. Crown is estimated to be 3-6' deep and 400' wide. Photo: B. Fredlund

Natural slab avalanche down low on the Fin. Photo: B. Fredlund

This natural slab avalanche on Abiathar near Cooke City released adjacent to another avalanche that occurred last week. Photo: G. Antonioli

Photo: B. Fredlund

Photo: B. Fredlund

We saw this avalanche on Thursday April 11th in addition to many similar crowns throughout terrain north of Cooke City. Natural new snow avalanches 1-2 feet deep ran the past 1-3 days during a heavy spring snowstorm. Photo: GNFAC

We saw this crown on Thursday April 11th in addition to many similar crowns throughout terrain north of Cooke City. Northeast aspect, 10,000' elevation. Natural new snow avalanches 1-2 feet deep ran the past 1-3 days during a heavy spring snowstorm. Photo: GNFAC

Natural avalanche of new snow on north aspect of Abiathar Peak near Cooke City. Photo: B. Fredlund

Natural wet slide activity on a west aspect around 8,600' near Cooke City. Photo: B. Fredlund

From e-mail: "some natural, wet slab avalanche activity from yesterday on Mt. Republic.  North facing, 8,000'.  Triggered by wet loose slides from above." Photo: B. Fredlund

From e-mail: "Some natural, wet slab avalanche activity from yesterday on Mt. Republic.  North facing, 8,000'.  Triggered by wet loose slides from above." Photo: B. Fredlund

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

Photo: GNFAC

Photo: GNFAC

Photo: 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

Near Cooke City we found a generally stable snowpack, similar to the rest of the advisory area. For the next few days avalanches will be confined to new snow that falls. These slides can be dry or wet loose slides, or fresh wind slabs. Carefully assess the stability of the new snow before riding steep terrain. Photo: GNFAC

Outside Cooke City up Zimmer Creek, a skier spotted this cornice fall which triggered a small pocket down low. Photo: F. Madsen

Many wet loose and wet slab avalanches were seen near Zimmer Creek (north of Cooke City) on south and east aspects. Temperatures were warm at 10,000 feet. Photo: F. Madsen

This photo near Lionhead, is indicative of the wet loose avalanches we are seeing on many low elevation, south facing slopes throughout our advisory area. Daytime temperatures near 50F will make avalanches like this more frequent and widespread in the coming days.

A small wet loose and slab avalanche on a SW facing slope near Daisy Pass. These slides were observed on March 17th, 2019. The wet loose looked at least a day or two old, the small slab a bit older. The slab broke ~18" deep at the ground, near some rocks. This slope had an unusually shallow snowpack.

Low angle metal roofs have heavy, thick slabs of snow that built up during persistent cold temperatures. These slabs will slide during warm temperatures. Be on the lookout for overhead hazard and be cautious where you walk or park your car during warm sunny days. An additional urban hazard are large icicles are that will break during warm days. Photo: A. Schauer