Trip Planning for Northern Madison

From email: “These pics are from last June 10-11, after the pass reopened on Friday. I was skiing the Gardner headwall at 5:30, solo, when this monster released. Yah. The initial cornice collapse triggered and entrained a secondary slab of varying thickness whose crown is seen in one of the photos.”

From obs 5/7/23: "Natural R3-4, D4 ripped out a large chunk of the south face of Wilson during the last warm period I would assume. Debris everywhere and one large boat-sized pile even scoured a path further down than the rest of the debris. Looked to be a mix of wet loose and wet slab release from high up. Alpha angle at the bottom of the debris was 25 degrees" Photo: C. Ellingson

From obs 5/7/23: "Natural R3-4, D4 ripped out a large chunk of the south face of Wilson during the last warm period I would assume. Debris everywhere and one large boat-sized pile even scoured a path further down than the rest of the debris. Looked to be a mix of wet loose and wet slab release from high up. Alpha angle at the bottom of the debris was 25 degrees" Photo: C. Ellingson

From obs 5/7/23: "Natural R3-4, D4 ripped out a large chunk of the south face of Wilson during the last warm period I would assume. Debris everywhere and one large boat-sized pile even scoured a path further down than the rest of the debris. Looked to be a mix of wet loose and wet slab release from high up. Alpha angle at the bottom of the debris was 25 degrees" Photo: C. Ellingson

From obs 5/7/23: "Natural R3-4, D4 ripped out a large chunk of the south face of Wilson during the last warm period I would assume. Debris everywhere and one large boat-sized pile even scoured a path further down than the rest of the debris. Looked to be a mix of wet loose and wet slab release from high up. Alpha angle at the bottom of the debris was 25 degrees" Photo: C. Ellingson

Give Big Gallatin Valley is May 4-5. The Friends of the Avalanche Center are participating again this year and thank you for your support. Between 6pm on May 4 through 6pm on May 5 you can support your favorite local non-profits. Donate Here.

A skier took this photo on 4/16/23. The avalanche likely ran around 4/11 during high danger for wet snow avalanches. 

From obs: "Was able to spot a deep slab avalanche from Gallatin peak, slab was at the headwaters of S Fork Hellroaring (N aspect @ 9800) Hard to tell when this released as it was a few miles away, I would estimate the crown being around 10 feet. Observed a small storm slab on a north aspect as well (1-2 foot crown). Also saw a few dozen wet slides that released earlier this week, some tearing all the way to the ground." Photo: T. Saulnier

From obs 4/14/23: "Pretty much the entire wall skiers right of the prayer flags back into beehive slid. Wet slide. Multiple crown lines and long running." These probably occurred during hot temperatures 4/8-4/11.

From obs 4/14/23: "Pretty much the entire wall skiers right of the prayer flags back into beehive slid. Wet slide. Multiple crown lines and long running." These probably occurred during hot temperatures 4/8-4/11.

From obs 4/14/23: "Pretty much the entire wall skiers right of the prayer flags back into beehive slid. Wet slide. Multiple crown lines and long running." These probably occurred during hot temperatures 4/8-4/11.

From Big Sky Ski Patrol: "Temps remained a little cooler than yesterday and generally topped out in the mid 40’s F. That didn’t stop the free water from moving
and continuing to destabilize the snowpack, primarily on solar aspects below 10,000’. Near full depth to full depth wet loose avalanches continued to naturally release in what was left of the A-Z’s as well as LRT which had not seen any activity yesterday." Photo: BSSP

A skier at Big Sky Resort saw three new wet snow avalanches on 4/10. Photo: J Aid

From an email referencing closed terrain within Big Sky Resort: "Numerous full depth wet loose naturals ran during the day on steep solar aspects in closed terrain including the Upper and Lower A-Z’s, Dirtbag Wall, Castro’s Shoulder and both Pinnacles. In addition, we pushed on numerous lower mountain road cuts that would generally run full depth onto the roads below." Photo: Big Sky Ski Patrol 

A pilot snapped some photos of a deep slab avalanche that released on April 6. He noted, "Too many point releases to count in every range I’ve crossed today…" Photo: Austin Timm, Yellowstone Air Service

A pilot snapped some photos of a deep slab avalanche that released on April 6. He noted, "Too many point releases to count in every range I’ve crossed today…" Photo: Austin Timm, Yellowstone Air Service

A pilot snapped some photos of a deep slab avalanche that released on April 6. He noted, "Too many point releases to count in every range I’ve crossed today…" Photo: Austin Timm, Yellowstone Air Service

From email: "...cornice collapse. One block in the debris pile was probably the size of my airplane - a giant ass snowball." Photo: Austin Timm, Yellowstone Air Service

From Obs: "Today we observed wet loose avalanche activity on the southerly aspects in the mountains around Pioneer mountain. We also observed one dry slab avalanche on a NE aspect of Sphinx mountain at approximately 9,000’." Photo: YCSP

From obs 4/7/23: "...3 separate deep slab avalanches since the most recent loading event (likely 4/3). Photos are attached.... The real show stopper was on the E face of Jumbo.... HS-N-R4-D3.5-O/G. Approximate crown width of 1000ft and average depth of 6-8ft. Total run of around 2000ft. A few photos attached. other slides of note, a few D1-1.5 WL slides low in the basin SW facing. Also, an older deep slab on N facing terrain just south of Hell Roaring Lake, D2-D2.5." Photo: T. McCutcheon 

From obs 4/7/23: "...3 separate deep slab avalanches since the most recent loading event (likely 4/3). Photos are attached.... The real show stopper was on the E face of Jumbo.... HS-N-R4-D3.5-O/G. Approximate crown width of 1000ft and average depth of 6-8ft. Total run of around 2000ft. A few photos attached. other slides of note, a few D1-1.5 WL slides low in the basin SW facing. Also, an older deep slab on N facing terrain just south of Hell Roaring Lake, D2-D2.5." Photo: T. McCutcheon 

From obs 4/7/23: "...3 separate deep slab avalanches since the most recent loading event (likely 4/3). Photos are attached.... The real show stopper was on the E face of Jumbo.... HS-N-R4-D3.5-O/G. Approximate crown width of 1000ft and average depth of 6-8ft. Total run of around 2000ft. A few photos attached. other slides of note, a few D1-1.5 WL slides low in the basin SW facing. Also, an older deep slab on N facing terrain just south of Hell Roaring Lake, D2-D2.5." Photo: T. McCutcheon 

 

From obs 4/7/23: "...3 separate deep slab avalanches since the most recent loading event (likely 4/3). HS-N-R2-D2.5-O @ around 10,000ft. " Photo: T. McCutcheon

From obs 4/7/23: "...3 separate deep slab avalanches since the most recent loading event (likely 4/3). Photos are attached. The first that we sighted was on the N/NE face of Jumbo. It appears to be cornice fall triggering a windslab that stepped down, HS-N-R2-D2-O @ around 10000ft on the N/NE face of Jumbo." Photo: T. McCutcheon 

This natural avalanche was observed in the afternoon around 1500. It was not seen earlier in the day and is thought to occurred at some point after 1200. It was seen from a distance on Pioneer mountain. It occurred on an E facing slope around 9600’. Active wind transport was noted on the ridge line above the avalanche. It looked to be around a R3-D2. Photo: R. Freeman

**Reporting this from a friend of a friend. Not my photo, nor was I involved.**
 

one skier got caught above large bottom cliff, carried all the way down over cliff to the apron. Said skier walked away completely unharmed. Not buried. 
 

north face of that bowl, near cornrows. 

Additional info from BSSP: 

"There was a large, deep slab avalanche snowboard triggered in Lone Lake Cirque this afternoon. The
slide ripped in a secondary start zone below ridgetop, and ran far into the flats, and may have run a

bit uphill, where it encountered the rock glacier moraine in the runout. It looks to be a R4, D2.5."

From IG:

Think this was a recent natural up buck I saw today. Didn’t get close enough to see but looked like it was a big crown… down low 8900ish SE

A skier remotely triggered a 1-2' deep slab of wind-drifted snow that broke ~100' wide outside the boundaries of Big Sky Resort. Photo: Anonymous

From obs 3/26/23: "Saw a couple small natural slides breaking in the new snow. The one on the small slope beside the road actually appeared to have broken when a snow bike crossed the top just off the side of the road." Photo: J. Weingarten

From obs 3/26/23: "Saw a couple small natural slides breaking in the new snow.... occurred in the afternoon sometime" Photo: J. Weingarten

Photo: R. Lindsey

Photo: R. Lindsey

From GVSA groomer via text on 3/24/23: "Small slide in Buck just below 5 mile on the road cut. Likely natural. E Face about 42 degrees, 6-8" new up on top with 10 mph wind out of the SE. Cuttently snowing at .5"/hour (9pm)." Photo: D. Kristensen

Toured around beehive peak today. Viewed 1 older large avalanche and other smaller slides. All were north to east aspects

The foreground and ridges are scoured from the recent wind. Cedar Falls is frozen fat with views of the Madison Valley below. Photo: GNFAC

From Obs: "On Saturday we toured up Dudley Creek. At around 1pm we ski cut an isolated, wind loaded pocket on a SE aspect at approximately 9200ft elevation and released a wind slab (see photo). The slab was about 20 feet wide, about 1 foot at it's deepest, and ran for about 200 feet. Staying wary of wind loading, we dug a pit on a NE aspect, in a spot without evidence of significant wind loading, and received an ECTNX. Although we did not identify any failure on buried weak layers in this location, it will remain something to watch for with more snow and warmer temps on the way." E Schreier

On Buck Ridge today (3/5/23) we found fresh, unstable drifts. This fresh slab was 4-6" deep. Cracking like this is a sign that wind slabs will avalanche on steeper slopes. Photo: GNFAC

Skier triggered avalanche on Elephant Mtn. 3/4/23. SS-ASu-R2-D1.5-I

Vertical Fall: ~700' Distance Traveled: ~1000' Aspect: 15 N Elevation of start zone: 9645'

Skier triggered deep slab avalanche on NE face of Hyalite Peak 3/4/23.

From FB message 3/4/23: "Buck ridge. East facing slope. Beaver creek area. Sled triggered. No burials."