Trip Planning for Lionhead Range

as of 5:00 am
Feb 111″ | 15-40 W
Feb 10 0″ | 10-30 W
Feb 9 0″ | 10-30 W
8775′  04/03 at 10:08
23℉
SW - 7mph
Gusts 10mph
7750′   06/28 at 19:00
66℉
0″ Depth
Bottom Line:

Past 5 Days

Tue Feb 8

Low
Wed Feb 9

Low
Thu Feb 10

Low
Fri Feb 11

Low
Thu Apr 21

None

Relevant Avalanche Activity

Lionhead Range
Lionhead Ridge
Small Snowmobile Triggered Avalanche
Incident details include images
Lionhead Ridge
SS-AMu-R1-D1-I
Coordinates: 44.7145, -111.3180
Caught: 0 ; Buried: 0

From obs: "Today I watched as a sledder dropped a cornice causing the cornice to fall triggering an
avalanche chasing him down the hill. The snowpack consisted of a wind slab on top of near-surface
facets and a couple of buried layers of surface hoar ."


More Avalanche Details
Lionhead Range
Ski Hill
Fatal Avalanche Ski Hill
Incident details include images
Incident details contain video
Ski Hill
SS-AMu-R1-D2-O
Elevation: 8,100
Aspect: E
Coordinates: 44.7016, -111.2930
Caught: 1 ; Buried: 1; Killed: 1

On Sunday, one snowmobiler in a group of four was caught and killed in a small avalanche on Ski Hill at the south end of Lionhead Ridge. He was on a 45-degree slope when it released and partially buried him against a tree. The slide was only 4"-11" deep, 75 feet wide and ran 300 feet vertical. His head was a foot under the snow. The avalanche was not witnessed and the victim was buried an estimated 15-25 minutes before he was uncovered. Rescue efforts were not successful. The group was familiar with the area and had rescue gear. The shallow, steep slide ended in trees, a terrain trap . Our deepest condolences go out to the family and friends of the rider. 

A detailed report can be read here.

 


More Avalanche Details
Cooke City
Goose Lake
Partial Burial on Sawtooth Mountain near Goose Lake
Incident details include images
Goose Lake
SS-ASu-R2-D2-O
Elevation: 10,800
Aspect: SE
Coordinates: 45.1437, -109.9040
Caught: 1 ; Buried: 1; Killed: 0

This morning while ascending a line on Sawtooth Mountain (Lower Novocain) we triggered an avalanche (ASu-SS-R2-D2-O)  that caught and carried my partner an estimated 180M and partially buried him. His leg and hand were unburied and excavation of the head was done in less than 2 minutes of the incident. The avalanche only involved new snow from the last 48hrs and was triggered on a MF crust/facet combo 30cm down(formed 1/30/22). The avalanche was 30cm at its deepest and 20-30M wide and ran 250M. We were lucky to find both skis and poles a little ways downslope. No injuries were sustained.

We both agree that we were trying to outsmart the instability that was present on steeper S facing terrain and should have turned around much sooner, we were very lucky. There was 30+cm HST in favored areas and the high winds from 1/31/22 formed some sensitive windslabs in specific areas. 

 


More Avalanche Details

Relevant Photos

Displaying 1 - 40
  • Chris Hericks, snow ranger on Beaverhead Deerlodge NF, points to the lower of two surface hoar layers. We are finding similar layering throughout our entire forecast area. The top 18" of the snowpack is weak and will quickly become unstable when it snows. Photo: GNFAC

  • Crown of the avalanche on Ski Hill. The snow rangers in the photo are standing near the victim burial site. Photo: GNFAC

  • Looking up from the bottom of the avalanche that killed one snowmobiler on Ski Hill. The crown is visible at the top of the hill. The men in the photo are standing near the trees where the victim was buried. Photo: GNFAC

  • The backpack pictured marks the place where the avalanche victim was buried. Photo: GNFAC

  • Identifying snow crystals in the layer that failed at the crown of the avalanche on Ski Hill. The avalanche broke on weak, faceted crystals near the surface. Photo: GNFAC

  • Debris from the fatal avalanche on Ski Hill. The backpack marks the place where the victim came to rest. Photo: J. Norlander

  • Identifying and recording grain types in the snowpack at the site of the Lionhead avalanche fatality. Photo: J. Norlander

  • The crown is not visible (it is down and right) but the X marks the approximate spot the rider was found. Photo: GNFAC

  • The crown was measured 4-11 inches deep and 75 feet wide. Photo: GNFAC

  • Looking at a weak layer of facets that the avalanche propagated on. Photo: GNFAC

  • Looking at the crown from below. Photo: GNFAC

  • From Obs: "Today I watched as a sledder dropped a cornice causing the cornice to fall triggering an avalanche chasing him down the hill. The snowpack consisted of a wind slab on top of near-surface facets and a couple buried layers of surface hoar." Photo: B Rasmussen

  • The avalanche was triggered by a snowmobiler on a small, but steep slope that carried him into the trees in picture. The avalanche was shallow and wide. The rider was partially buried but did not survive. Photo: GNFAC

  • On Sunday, February 6, Gallatin Country Sheriff Search and Rescue and the GNFAC responded to a avalanche in Lionhead. A snowmobiler was killed on a small steep slope when a shallow avalanche carried him into a terrain trap of trees. Photo: GNFAC

  • This morning while ascending a line on Sawtooth Mountain (Lower Novocain) we triggered an avalanche (ASu-SS-R2-D2-O)  that caught and carried my partner an estimated 180M and partially buried him. His leg and hand were unburied and excavation of the head was done in less than 2 minutes of the incident. The avalanche only involved new snow from the last 48hrs and was triggered on a MF crust/facet combo 30cm down(formed 1/30/22). The avalanche was 30cm at its deepest and 20-30M wide and ran 250M. We were lucky to find both skis and poles a little ways downslope. No injuries were sustained.

    We both agree that we were trying to outsmart the instability that was present on steeper S facing terrain and should have turned around much sooner, we were very lucky. There was 30+cm HST in favored areas and the high winds from 1/31/22 formed some sensitive windslabs in specific areas. 

     

  • Graph of Snow Water Equivalent (SWE) at SNOTEL sites in the GNFAC forecast area from October 1, 2021 to January 30, 2022. It highlights the extended dry conditions in January that contributed to weak layers forming at the top of the snowpack. GNFAC

  • We rode at Lionhead today (Jan. 29, 2022) and found very weak snow on the surface which is not a problem now, but will be when we get more snow. Photo: GNFAC

  • Riders in the Lionhead area noted that a layer of feathery surface hoar is continuing to grow. If this gets buried by the next snowstorm it will become a new weak layer. Photo: G Ewsuk

  • Riders reported on 1/15/22: "Some surface hoar is forming on nearly every aspect at all elevations. over 1 cm thick in some areas." Photo: B. Rasmussen

  • Riders reported on 1/15/22: "Some surface hoar is forming on nearly every aspect at all elevations. over 1 cm thick in some areas." Photo: B. Rasmussen

  • Settlement rings around the base of trees near Cooke City, January 15, 2022. Photo: B. Fredlund

  • Ian Hoyer stands in the 7 foot deep snowpit we dug to look at layering and stability. Stability was good. We dug at 9300' off the Sawtelle Peak Road to keep tabs on stability since we put out warnings and basic information for this area on our Trip Planning page. Photo: GNFAC

  • A wind swept ridgeline at the head of Targhee Creek near Lionhead. 1/11/22. Photo: GNFAC

  • Cornices along Lionhead Ridge. 1/11/22. Photo: GNFAC

  • A layer of near surface facets is buried about a foot down on some slopes near Lionhead. 1/11/22 Photo: GNFAC

  • Small natural storm slab avalanche seen near Lionhead. 1/6/22. Photo: C. Leonard

  • The West Yellowstone Beacon Park is up and running for the season! 

    Photo: J. Norlander (1/6/22)

  • This avalanche broke wide in a northerly facing bowl off Lionhead Ridge. It looks to have broken a foot or less deep. The propogation indicates a uniform weak layer, likely near-surface facets or surface hoar. Photo: B. Fuglie

  • A sled was recovered uphill of the 2 avalanche victims in the same area it was stuck. The sled was found with a probe line and is buried 3-4 feet deep. The avalanche crown can be seen in the upper slopes above them. Photo: GNFAC

  • The crown of the avalanche that killed two snowmobilers on December 27, 2021 was 300 feet wide and 4-5 feet deep. Photo: GNFAC

  • These are the two sites where the 2 snowmobilers were recovered. They were buried 4-5 feet deep in debris piles that measured 9 feet deep. Photo: GNFAC

  • Ian Hoyer stands next to the crown where we dug a snowpit and investigated the snow structure. The crown averaged 4-5 feet deep. Near his right knee is the layer of weak faceted snow that broke 40 cm above the ground. Above this layer was a thick slab of windblown snow. Photo: GNFAC

  • Dave Zinn of the GNFAC gets 3 layers breaking in his Extended Column Test. About 3 feet of snow fell in the last 4 days which got blown into wind slabs. The weight of the new snow is also creating instability on a weak layer of sugary facets near the ground. Photo: GNFAC

  • Riders in the Lionhead area observed 5-6 naturally occurring avalanches that likely failed on 12/15 at the tail end of a 3' snowstorm. Photo: S. Tyson

  • Located off Lionhead Ridge outside West Yellowstone, this natural avalanche likely released after the large storm ended Wednesday, December 15. This slope is SE facing and the crown is about 9,400 feet. Faceted snow at/near the ground was the likely weak layer that avalanched. Photo: GNFAC

  • Snowpack on Two Top Mtn. near Island Park, ID on 12/17/21. More than 3 feet of snow fell last week and it was right side up and generally stable. There is some weak snow and crusts near the ground, but we are not seeing signs that these layers are unstable yet. Photo: E. Knoff

  • A skier in the Southern Madison Range remotely triggered this avalanche in the Bacon Rind area from a flat bench above the slope. It broke over 50-75' away where the slope got steeper. Human-triggered avalanches are likely. Avoid steep terrain until the snowpack stabilizes. Photo: Anonymous 

  • From obs: 12/12/21: "Heavy wind loading from gusty SW winds and recent snowfall. Made for some touchy conditions. This was at 9100’ between Sage and Sunlight basins." Photo: JR Mooney

  • At Lionhead Ridge, strong winds are drifting snow into unstable slabs. On steep rollovers, we observed shooting cracks and one large collapse, or "whumph." With more wind and snow in the forecast, expect conditions to get more dangerous before they improve. Photo: GNFAC

  • New snow was blown into thick drifts that can be triggered by skiers or riders. Cracking like this is a sign that drifts are unstable and could slide on steeper slopes. Photo: GNFAC

WebCams


Rendezvous Ski Trail, W. Yellowstone

Snow Observations- Lionhead Range

Island Park
Tin Cup Pass
Good stability outside Island Park
Incident details include images

From the Gallatin NF Avalanche Center:

We rode up Yale Creek, then to the Mt. Jefferson Bowl, then to Tin Cup Pass north of Mt Raes. We  saw no avalanche activity or signs of instability. It was calm out and the wind was not moving snow. The debris piles on Mt. Jefferson were from an avalanche cycle the end of December and they are still visible. January has been dry! 

Our stability test did not break on the surface hoar . There needs to be more snow on top of it. Possibly on a wind drifted area, but in general, the stability is good until we get more snow. 

Full Snow Observation Report

Snowpit Profiles- Lionhead Range

 

Select a snowpit on the map to view the profile image

Weather Forecast Lionhead Range

Extended Forecast for

10 Miles WNW West Yellowstone MT

  • Tonight

    Tonight: A 20 percent chance of showers before 10pm.  Partly cloudy, with a low around 47. Light and variable wind becoming west southwest 8 to 13 mph in the evening.

    Slight Chance
    Showers then
    Partly Cloudy

    Low: 47 °F

  • Wednesday

    Wednesday: A slight chance of showers between 11am and 5pm.  Mostly sunny, with a high near 64. Breezy, with a southwest wind 13 to 18 mph increasing to 24 to 29 mph in the afternoon. Winds could gust as high as 40 mph.  Chance of precipitation is 20%.

    Slight Chance
    Showers and
    Breezy

    High: 64 °F

  • Wednesday
    Night

    Wednesday Night: Mostly clear, with a low around 40. Breezy, with a west southwest wind 19 to 24 mph becoming north northwest 9 to 14 mph after midnight. Winds could gust as high as 33 mph.

    Mostly Clear
    and Breezy
    then Mostly
    Clear

    Low: 40 °F

  • Thursday

    Thursday: Sunny, with a high near 62. Northeast wind 6 to 15 mph becoming west southwest in the afternoon. Winds could gust as high as 21 mph.

    Sunny

    High: 62 °F

  • Thursday
    Night

    Thursday Night: Mostly clear, with a low around 42. West wind 8 to 15 mph becoming northeast after midnight. Winds could gust as high as 21 mph.

    Mostly Clear

    Low: 42 °F

  • Friday

    Friday: Sunny, with a high near 65. East northeast wind 8 to 13 mph becoming west southwest in the afternoon.

    Sunny

    High: 65 °F

  • Friday
    Night

    Friday Night: Mostly clear, with a low around 44. West southwest wind 8 to 14 mph becoming northeast after midnight. Winds could gust as high as 20 mph.

    Mostly Clear

    Low: 44 °F

  • Saturday

    Saturday: A slight chance of showers and thunderstorms after noon.  Mostly sunny, with a high near 67. Northeast wind 7 to 15 mph becoming southwest in the afternoon. Winds could gust as high as 21 mph.

    Sunny then
    Slight Chance
    T-storms

    High: 67 °F

  • Saturday
    Night

    Saturday Night: A slight chance of showers and thunderstorms before midnight.  Partly cloudy, with a low around 46.

    Slight Chance
    T-storms then
    Mostly Clear

    Low: 46 °F

The Last Word

We completed our investigation of the avalanche fatality at Ski Hill in Lionhead. A detailed report is HERE, the field video is on our YouTube channel and the incident is recorded on our Accident Reports page.


  <<  This is the most recent forecast.