Regional Conditions for Lionhead Range

as of 5:00 am
Feb 156″ | 10-20 W
Feb 14 14″ | 15-20 SW
Feb 13 3″ | S
8775′     2/16 at 4:00
10 ℉
NW - 3 mph
Gusts 9 mph
7750′   02/16 at 3:00
17℉
72″ Depth
Bottom Line: Natural and human triggered avalanches are likely on all wind loaded slopes. Areas loaded by west-southwest winds will be the most susceptible to holding wind drifted snow. Human triggered avalanches are also likely on non-wind loaded slopes. During these conditions, avoiding steep slopes and avalanche run out zones is essential. This includes staying off small steep slopes like road cuts and creek beds that may seem harmless during more stable conditions.
Primary Problem: Wind-Drifted Snow

Past 5 Days

Mon Feb 11

Considerable
Tue Feb 12

Considerable
Wed Feb 13

Considerable
Thu Feb 14

High
Fri Feb 15

High

Avalanche Activity- Lionhead Range

Centennial Range
Centennials - Idaho
Snowmobiler caught and buried in Centennials
Incident details include images
Centennials - Idaho
SS-AMu-R2-D2-O
Caught: 1 ; Buried: 1

This was shared with me from one of our Fremont County Search & Rescue members. I have no further information.

Video URL

https://www.facebook.com/nate.nygard.5/videos/2347244235309969/


More Avalanche Details
Lionhead Range
Lionhead Ridge
Snowmobile triggered at Lionhead
Incident details include images
Incident details contain video
Lionhead Ridge
HS-AMu-R3-D2.5-O
Elevation: 9,000
Aspect: E
Caught: 0 ; Buried: 0
More Avalanche Details
Lionhead Range
Lionhead Ridge
Natural avalanches at Lionhead
Incident details include images
Incident details contain video
Lionhead Ridge
SS-N-R2-D2
Elevation: 9,000
Caught: 0 ; Buried: 0

GNFAC forecasters' observation: On 2/8/19 we observed 3 recent avalanches with unknown triggers (assumed natural) and one snowmobile triggered avalanche (listed separately as AMu on 2/6/19) along Lionhead Ridge. Three of them, including the snowmobile triggered slide, broke 3-4+ feet deep on sugary weak snow in the lower 1/3 of the snowpack. One avalanche broke 2' deep in the recent storm snow.


More Avalanche Details

Photos- Lionhead Range

Displaying 1 - 40 of 4.61168601843E+18
  • This snowmobile was fully buried, along with its rider on February 7th, 2019, in the Centennial Range.

  • Photo of the snowmobile triggered slide that fully buried a rider on February 7th, 2019.

  • A large snowmobile triggered avalanche in the Gravelly Range (Outside of advisory area) on February 10th, 2019.

    From email: "One rider was involved in the incident and was fortunate to be on the upper left side of the bowl when he saw the slide start. ... the crown was about 325 wide and varied in depth from 1 to 4 or 5 feet.  The ridge line was wind loaded and this was an issue we had discussed as a group and wanted to avoid.  We had read the reports for the day and knew that wind loading as well as a persistent week layer were both concerns. .... The rider involved entered the area from around where the road switchbacked and did not realize what was above him due to reduced visibility."

  • This avalanche broke on weak snow in the lower 1/3 of the snowpack after a storm dropped 2-3' of heavy snow between 2/3 and 2/5/19. Photo: GNFAC

  • Multiple large avalanches occurred in the Lionhead area near West Yellowstone after 2-3’ of heavy snow earlier this week. Photo: GNFAC

  • This avalanche was triggered by snowmobilers on 2/6. 2-3’ of heavy snow earlier this week fell on a weak snowpack making large avalanches possible. Photo: GNFAC

  • This avalanche was triggered by snowmobilers on 2/6. 2-3’ of heavy snow earlier this week fell on a weak snowpack making large avalanches possible. Photo: GNFAC

  • From an email, "Observed this large avalanche while driving north from Jackson Hole today.  (on the E, NE aspect of Sawtell Peak, in the Centennial Mountains)"

    Likely released in the last day or so with the Avalanche Warnings on Sun, Mon and Tuesday. Photo: B. Fredlund

  • Snowmobilers in the Lionhead area got unstable test results, easily propagating fractures in ECT tests on a weak layer buried about 50 cm deep. Photo: J. Norlander

  • This photo was taken by a FS snow ranger on Feb 1st. These avalanches likely occurred towards the end of a period of steady snowfall from Jan 16th to 28th. From e-mail: "The Reas Peak area had 7 slides that I could see from the bottom of the drainage, most of them looked to have occurred with the last storm and had a northerly influence to their aspect. The largest and most recent slide I included in the [above photo], Reas Peak is the highest peak on the left in the photo and the slide path is on a NE aspect. If you look close at the photo you can see a 2-3’ crown on the far left side of the frame on the north aspect of Reas from another slide." Photo: C. Hericks

  • This photo of an avalanche on the north side of Reas Peak was taken by a FS snow ranger on Friday, Feb 1. It likely occurred towards the end of a period of steady snowfall from January 16th to 28th. Photo: C. Hericks

  • Mount Jefferson (just north of Reas Peak) is the peak in the background. Nasty avalanche on persistent weak layer in the foreground. Photo: B. VandenBos

  • Large avalanche on Bald Peak in the Lionhead area near West Yellowstone. Photo: B. VandenBos

  • A very deep natural avalanche was observed on Sheep Mountain, on January 28th. 

    From email: "This was southern facing slope of sheep mountain... Crown was at least 8’... very heavy wind loading."

    Photo: H. Menssen

  • Cracking and collapsing on a 31-degree slope near the Lionshead area down south. The slab was 3-4' deep, and the slope was on the verge of being steep enough to avalanche. From the email: " fractured about 20’x10’ area initially, maybe 3-4’ deep. We got off the hill and it continued to fracture in bigger spots but did not slide more than a foot total." Photo: S. Thompson

  • Crown of avalanche that was triggered by a group of four skiers. Two were partially buried (1 injured, 1 killed) on 1/25/19. They were all ascending and near the top of the path when the avalanche broke. The top two skiers held onto trees as the avalanche pushed by them. Photo: GNFAC

  • Overview of avalanche path where a group of four skiers were caught, and two were partially buried (1 injured, 1 killed) on 1/25/19. Crown is marked by black line and location of partial burial/deceased is tip of red arrow. The other partially buried skier was 200' lower. They were all ascending and near the top of the path when the avalanche broke. The top two skiers held onto trees as the avalanche pushed by them. Photo: GNFAC

  • From an email:

    "...was riding with a group near the Two Top area and remotely triggered this slide as rode past this drainage on the top of the ridge. It was a north facing wind loaded slope in the 38 degree slope range. It broke about 12 inches deep and looked like it was from the last snow/wind loading." Photo: J. Norlander

  • From facebook: "natural avalanche down near reynolds pass. West facing slope, it faces hwy 87 and is named mile Creek trail by usfs. No snowmobiling and haven't ever seen anyone ski it."

  • This graph shows snow water equivalent (SWE) by date at the primary SNOTEL sites that we use in the GNFAC region. From October 1st, 2018 to January 12th, 2019. Steeper lines indicate bigger storms and flatter lines indicate periods of little to no snow. A large storm at the beginning of Novermber laid down a 1-3 foot base. Relatively dry and cold weather through November caused much of that snow to become weak. This weak snow was buried by a series of storms. Avalanches were seen during and following many of these storms. During dry weather between storms, more weak layers formed on the surface of the snowpack and were subsequently buried. (Graph created by GNFAC from NRCS provisional data).

  • One of many avalanches that broke during the last week's avalanche cycle at Lionhead. Natural and snowmobile triggered slides were reported between 1/7 and 1/9/19. On 1/6-1/7 the area got a foot of heavy snow followed by strong winds. This loaded an unstable snowpack that is poorly supported by 1.5' of sugary snow on the ground. Avalanches broke 2-3 feet deep on this weak snow, and propagated relatively wide. Photo: GNFAC

  • One of many avalanches that broke during the last week's avalanche cycle at Lionhead. Natural and snowmobile triggered slides were reported between 1/7 and 1/9. On 1/6-1/7 the area got a foot of heavy snow followed by strong winds. This loaded an unstable snowpack that is poorly supported by 1.5' of sugary snow on the ground. Avalanches broke 2-3 feet deep on this weak snow, and propagated relatively wide. Photo: GNFAC

  • A snowmobile triggered avalanche that broke during the last week's avalanche cycle at Lionhead. Multiple (5+) natural and snowmobile triggered slides were reported between 1/7 and 1/9. On 1/6-1/7 the area got a foot of heavy snow followed by strong winds. This loaded an unstable snowpack that is poorly supported by 1.5' of sugary snow on the ground. Avalanches broke 2-3 feet deep on this weak snow, and propagated relatively wide. Photo: GNFAC

  • A snowmobile triggered avalanche that broke during the last week's avalanche cycle at Lionhead. Multiple (5+) Natural and snowmobile triggered slides were reported between 1/7 and 1/9. On 1/6-1/7 the area got a foot of heavy snow followed by strong winds. This loaded an unstable snowpack that is poorly supported by 1.5' of sugary snow on the ground. Avalanches broke 2-3 feet deep on this weak snow, and propagated relatively wide. Photo: GNFAC

  • A snowmobile triggered avalanche that broke during the last week's avalanche cycle at Lionhead. Multiple (5+) Natural and snowmobile triggered slides were reported between 1/7 and 1/9. On 1/6-1/7 the area got a foot of heavy snow followed by strong winds. This loaded an unstable snowpack that is poorly supported by 1.5' of sugary snow on the ground. Avalanches broke 2-3 feet deep on this weak snow, and propagated relatively wide. Photo: GNFAC

  • In Cabin Creek (1/10/19) we found a recently buried layer of surface hoar as well as the weak, sugary snow that makes up the bottom 1.5' of the snowpack in the southern ranges. Avalanches are possible to trigger on the sugary facets near the ground. Both of these weak layers will persist and cause avalanches when we get more snow and wind loading. Photo: GNFAC

  • February 2, King and Queen of the Ridge at Bridger Bowl (fundraiser). Register with Bridger to hike in the event, and create a pledge page to raise funds with your Ridge laps.

  • A snowmobiler triggered a slide in Lionhead on Tuesday, January 8. Photo: D. Mintus

  • A sledder remote triggered several slides from the bottom of a south facing slope in the Centennial Range, Hell Roaring Creek. Photo: B. Marsh

  • A sledder remote triggered several slides from the bottom of a south facing slope in the Centennial Range, Hell Roaring Creek. Photo: B. Marsh

  • Avalanche triggered remotely by a snowmobiler near Lionhead Ridge on January 7, 2019. From email "24 inch crown and about 200 feet wide... on an easterly wind loaded slope"

  • A snowpit on Lionhead revealed two weak layers. One was under wind blown snow; the other was 1.5 feet above the ground on a thick layer of sugary facets. Photo: GNFAC

  • From e-mail: "This was a snowmobile triggered slide in a S aspect in the Blue Creek Drainage SE of Reas Peak in the Centennials.  No one was caught and no injuries as far as I can tell".

  • This was a recent snowmobile triggered avalanche In Tepee Basin, southern Madison range. This slide failed on facets near the ground and ran into a terrain trap. With more snow and wind in the forecast, it will be important to make conservative terrain selections. Photo: GNFAC 

  • This avalanche in Airplane Bowl off Lionhead Ridge, is south facing at 9,000'. The avalanche was 1-2' deep, 100' vertical and 150' wide (estimated). It likely broke late Sunday or Monday (12/31), during or immediately after the Avalanche Warning. Weak, faceted snow could not support the weekends snowstorm and there were widespread slides. Photo: GNFAC

  • Collapsing and cracking in Watkins Creek in Lionhead. The snow is weak and collapses like this indicate instability. Photo: B. Rasmussen

  • Collapsing and cracking in Watkins Creek in Lionhead. The snow is weak and collapses like this indicate instability. Photo: B. Rasmussen

  • The snowpack at 9,000' above Hebgen Lake near West Yellowstone is 60-70cm (~2 feet) deep. It is mostly weak, sugary facets and will struggle to support the weight of future storms. Photo: GNFAC

Videos- Lionhead Range

Weather Forecast Lionhead Range

Extended Forecast for

10 Miles WNW West Yellowstone MT

  • Overnight

    Overnight: A 50 percent chance of snow.  Mostly cloudy, with a low around 13. Wind chill values as low as -1. West southwest wind around 11 mph.  Total nighttime snow accumulation of 1 to 3 inches possible.

    Chance Snow

    Low: 13 °F

  • Saturday

    Saturday: Snow likely, mainly after noon.  Mostly cloudy, with a high near 15. Wind chill values as low as -1. Southwest wind 9 to 14 mph, with gusts as high as 21 mph.  Chance of precipitation is 70%. New snow accumulation of 1 to 2 inches possible.

    Snow Likely

    High: 15 °F

  • Saturday
    Night

    Saturday Night: A 50 percent chance of snow, mainly before 2am.  Patchy fog after 11pm.  Otherwise, mostly cloudy, with a low around 5. Wind chill values as low as -5. Southwest wind 6 to 10 mph.  New snow accumulation of less than one inch possible.

    Chance Snow
    and Patchy
    Fog

    Low: 5 °F

  • Sunday

    Sunday: Snow likely, mainly after 11am.  Mostly cloudy, with a high near 14. Wind chill values as low as -6. North wind 5 to 9 mph.  Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.

    Snow Likely

    High: 14 °F

  • Sunday
    Night

    Sunday Night: A 20 percent chance of snow before 11pm.  Mostly cloudy, with a low around -6. North northeast wind 8 to 10 mph.

    Slight Chance
    Snow then
    Mostly Cloudy

    Low: -6 °F

  • Washington's
    Birthday

    Washington's Birthday: A 30 percent chance of snow, mainly after 11am.  Mostly cloudy and cold, with a high near 8. New snow accumulation of less than one inch possible.

    Chance Snow

    High: 8 °F

  • Monday
    Night

    Monday Night: Partly cloudy, with a low around -8.

    Partly Cloudy

    Low: -8 °F

  • Tuesday

    Tuesday: A slight chance of snow after 11am.  Mostly sunny and cold, with a high near 9.

    Slight Chance
    Snow

    High: 9 °F

  • Tuesday
    Night

    Tuesday Night: A chance of snow, mainly after 11pm.  Mostly cloudy, with a low around -1.

    Chance Snow

    Low: -1 °F

The Last Word

The Friends of the Avalanche Center and Montana State Parks installed an avalanche danger sign outside Cooke City. It sits next to the beacon checker and will be seen by riders and skiers as they head out of town.


  <<  This is the most recent forecast.