Regional Conditions for Centennial Range

as of 5:00 am
Today0″ | 10-20 SW
Feb 20 0″ | 10-15 SW
Feb 19 0″ | N/A
8775′     2/13 at 22:00
15 ℉
SW - 10 mph
Gusts 18 mph
7750′   02/21 at 22:00
22℉
60″ Depth
Bottom Line: The snowpack is generally stable in the mountains around West Yellowstone. We’re a week out from the last reported avalanche. The weak snow at the ground is still there, but triggering an avalanche on it is unlikely. Watch out for the possibility of trigging small wet loose avalanches as the surface snow becomes wet with today’s warm temperatures and sunny skies.
Avalanche Concern: Persistent Weak Layer

Snow Observations- Centennial Range & Lionhead

Centennial Range
Centennials - Montana
Hellroaring yurt, centennial range

we observed approximately 20 inches of new snow from the storm Wednesday 2/5 to Sat 2/8 morning. The storm ended very warm, even with about 10 minutes of rain Sat morning. This formed a thin breakable rain crust up to 9,000 feet. Over the day Saturday, we received an additional 2 inches of low density snow and heavy wind from the NW as a cold front passed. Sunday was clear, calm, cold, but by mid day had warmed south facing slopes to the point of wet roller balls. The only natural slide observed was in the buffalo hump area on a NE facing slope below a cliff band. It looked to be 2 feet deep, 200 feet wide.

Pit data:

On Sunday morning, pit dug on a SE facing slope 8400 feet. 152cm snowpack. ECT 13 broke at 125 cm, Quality 2. This broke on a rain/sun crust. Facets 0-30cm. The crust formed Saturday morning was prevelant and would be of concern after an additional load.

Pit on N facing aspect at 7800 feet showed 180cm depth and stable. Conducted CT and shovel shear with no results. However, Crust from Sat morning rain was evident and could be of concern after additional load.

We found the best conditions to be in protected bowls on West to North to East aspects.

Full Snow Observation Report
Centennial Range
Centennials - Montana
Hellroaring
Incident details include images

Spent the afternoon in Hellroaring drainage trekking to the hut. Around 2:30 the clouds cleared allowing us to view higher peaks and bowls. Did not observe any crown lines on steep cut banks above the creek, or higher up. Expected to hear and see more signs of instability, but did not. Suprisingly little wind and drifting during the last storm, 18-24" consolidated new snow in the last 2 weeks as evidenced by accumulation on the hut. Snow depth at 7500' in a SW facing meadow was 150 cm. Fairly close to what the White Elephant Snotel reports just a few miles away. Didn't have time to do pit tests since I was dropping a group off and my dog ruins any sense of an "undisturbed column", however in general this new snow apprears to have developed into a very dense and stiff slab 18-25" everywhere likely hiding the lurking dragon in low angle terrain we stayed in during our approach.

Full Snow Observation Report
Centennial Range
Hellroaring Creek
Tin Cup Pass-Mt. Jefferson-Centennials

Aspect: north
Slope: 30
HS: 160cm
Basic snow structure: round 160cm-50cm rounds, 50-40cm facets, 40-0cm large facets.
ECTX
CT13 at 40cm not planar

Full Snow Observation Report
Centennial Range
Reas Peak
Read Peak, Centenials -Island Park, ID
Incident details include images

Pictures sent to me from an out of state friend. No other info at this time other than that he was able to ride through it uphill.

Full Snow Observation Report
Centennial Range
Centennials - Montana
Hellroaring Drainage
Incident details include images

During a 3+ mile tour from 6500' to 8500' we did not witness any old or recent avalanche activity on upper elevation slopes, or low elevation areas such as steep banks leading to the Hellroaring Creek where we have in previous season, that isn't to say that high winds haven't filled any observable crown lines in. The snow depth in this region was surprisingly shallow given the reported snow depths at reporting snotel stations. i.e., White Elephant Snotel. It seems as though high wind has scoured exposed areas including ridge tops West facing slopes heavily. Between 7,500' & 8,300', all NW-SW aspects had roughly 65cm of unconsolidated snow. The lower half of the snow pack consisted of various sized facets depending on aspect. In general, we observed a snowpack with poor structure and fair strength. Pit results did not yield propagation in any layers. Compressions tests showed low quality shearing at the interface between the new snow and the older faceted layers.

Full Snow Observation Report
Centennial Range
Two Top
Centennial Range and Two Top

As you're well aware, the snowpack around West is crap. We found conditions on Two Top to be very similar to Lionhead. We didn't see any avalanche activity but did get some large collapses and unstable test results. Surprisingly, conditions were quite different in the Centennials. We rode on the west side of the range and found 30-50 cm's of snow on south and west-facing slopes. These aspects lacked weak layers near the ground and had a relatively shallow but stable snowpack. As we ventured onto shadier slopes (north-east) we found a different structure. Snow from early in the season had faceted and was capped by a 30-50 cm slab. In general, the snowpack in Centennials is better than Lionhead and Two Top.

Full Snow Observation Report

Avalanche Activity- Centennial Range & Lionhead

A child triggered a small avalanche
Incident details include images
SS-AFu-R1-D1
Caught: 0 ; Buried: 0

On private property, this small child triggered a slide and climbed out of the debris, not buried. A very close call! On the heels of this large snowstorm there are possibilities of children getting caught on road cuts or any open hill!


More Avalanche Details
Northern Gallatin
Elephant Mountain
Several avalanches on Elephant Mtn on way to Mt. Blackmore
Elephant Mountain
SS-N-D2-I
Elevation: 8,800
Aspect: NW
Coordinates: 45.4382, -110.9900
Caught: 0 ; Buried: 0

"Noted several avalanches (NW aspect ~ 8800') off of Elephant that traveled quite far into the trees where the summer trail typically runs, all appear to be new snow, D1- D2 in size, average 2' crowns, running on old/new interface from  Feb 2. They appear to have run midstorm, sometime yesterday (photos 1,2,3).  Above 9000', W Winds were crafting fresh wind slabs that were most reactive on a midstorm crystal/density change that buried a layer of stellars ~ 1' deep in shallower spots,  topped with denser snow." 


More Avalanche Details
Northern Gallatin
Wheeler Mountain
Natural avalanches on Wheeler Mtn, N. Gallatin
Incident details include images
Incident details contain video
Wheeler Mountain
SS-N-R3-D2
Elevation: 8,000
Aspect: SE
Coordinates: 45.5097, -111.0820
Caught: 0 ; Buried: 0

"Noted two SS-D1.5/2 naturals (presuming based on lack of any sort of tracks) on Wheeler, typical spots for these conditions, both SE aspect around 8000'."

Dave Zinn dug a snowpit lookers right of the slides in the next path on Wednesday, 2/5, a couple days before the storm. He found weak snow that was ready to avalanche.


More Avalanche Details

Photos- Centennial Range & Lionhead

Displaying 1 - 40
  • We rode into Lionhead and found good stability. A sledder highmarked up the hill and then came down right next to us, confirming our results. Wind-loading from yesterday is still a concern, and so are the facets near the ground, although less so than a couple weeks ago. Photo: GNFAC

  • "Noted two SS-D1.5/2 naturals (presuming based on lack of any sort of tracks) on Wheeler, typical spots for these conditions, both SE aspect around 8000'." Photo: G. Antoniolli

  • "Noted several avalanches (NW aspect ~ 8800') off of Elephant that traveled quite far into the trees where the summer trail typically runs, all appear to be new snow, D1- D2 in size, average 2' crowns, running on old/new interface from  Feb 2. They appear to have run midstorm, sometime yesterday (photos 1,2,3).  Above 9000', W Winds were crafting fresh wind slabs that were most reactive on a midstorm crystal/density change that buried a layer of stellars ~ 1' deep in shallower spots,  topped with denser snow." Photo: G. Antoniolli

  • "Natural avalanche. North facing slope. Around half mile wide. Photos don't show half of the slide. Broke on the ground facets. Crown was between 3 and 15 feet deep. We didn't get a photo of the deepest crown. Ripped trees out around 5" diameter." Photo: Reed Malmstrom

  • "Natural avalanche. North facing slope. Around half mile wide. Photos don't show half of the slide. Broke on the ground facets. Crown was between 3 and 15 feet deep. We didn't get a photo of the deepest crown. Ripped trees out around 5" diameter." Photo: Reed Malmstrom

  • On private property, this small child triggered a slide and climbed out of the debris, not buried. A very close call! On the heels of this large snowstorm there are possibilities of children getting caught on road cuts or any open hill!  Photo: Anonymous

  • We triggered this avalanche in the second Yellow Mule off Buck Ridge on 2/6/2020 It is on a small roll/cornice "in the flats". It broke within the current 2-3' storm snow. Photo: GNFAC

  • A snowmobiler triggered this avalanche in the second Yellow Mule off Buck Ridge on 2/6/2020 It is on a small roll/cornice "in the flats". It broke within the current 2-3' storm snow. Photo: GNFAC

  • We saw this natural crown that broke within the current 2-3' storm on a small terrain feature. It is in the second Yellow Mule off Buck Ridge on 2/6/2020. Photo: GNFAC

  • I took out my binoculars from our cabin on the west shore of Island Park Reservoir and noticed this huge slide in the bowl south of Reas peak. Started at the little tree band below the ridge, takes out 1/3 of the bowl, and runs into the Blue Creek terrain trap. I assume this is a natural avalanche as I don’t see tracks (hard to see in this light). Photo: M Elstad
  • I took out my binoculars from our cabin on the west shore of Island Park Reservoir and noticed this huge slide in the bowl south of Reas peak. Started at the little tree band below the ridge, takes out 1/3 of the bowl, and runs into the Blue Creek terrain trap. I assume this is a natural as I don’t see tracks (hard to see in this light). Photo: M Elstad
  • From riders involved: "Yesterday we were the ones in the big sky avalanche. There was no markings on the spot we were climbing. Further down the mountains there were climbs at the same angles of this slope. Thankfully the rider was above the slide when it started and managed to stay on top. Rider walked down the debris and we found the sled lower down in the trees. No injuries." Photo: Anonymous

  • From riders involved: "Yesterday we were the ones in the big sky avalanche. There was no markings on the spot we were climbing. Further down the mountains there were climbs at the same angles of this slope. Thankfully the rider was above the slide when it started and managed to stay on top. Rider walked down the debris and we found the sled lower down in the trees. No injuries." Photo: Anonymous

  • From obs. form: "[slope] Was marked up previously. We parked out near the bottom and a few guys not in our group start climbing. So we watch them climb. It breaks out. Guy ditches the sled and manages to stay up top. Sled goes down with the slide. Then the snow breaks in 2 other spots creating more slides." Photo: C. Carlson

  • The 10' deep avalanche in 2nd Yellowmule is almost completely filled in now. In its place are massive cornices overhanging the slope. Give these beasts a lot of extra room as they can break back far from the edge. Photo: GNFAC

  • Ian Hoyer stands in a snowpit in Beehive Basin. Avalanches are getting harder to trigger, but in more shallow areas we are still finding a poor snowpack structure. The stability test scores are climbing higher, but still propagating and we did not ski the adjacent slope. Photo: GNFAC

  • February 1, King and Queen of the Ridge at Bridger Bowl (fundraiser). This is the Friends of the Avalanche Center’s second biggest fundraiser of the year. Come on out and help us raise money by hiking and skiing laps on the ridge. Prizes, camaraderie and a good time is guaranteed. Register with Bridger to hike in the event, and create a pledge page to raise funds with your Ridge laps.

  • From email:

    "I wanted to make you aware of a snowmobile triggered slide in Lionhead today. Fortunately, I was not injured, was able to stay completely on top, climbed through the majority of the snow wash after seeing it begin to break, and relatively slowly slid down with the last of the moving snow while still on the machine. When I came to a stop, I stood up and was completely free of the snow. Our group is trained in avalanche safety, practiced beacon use prior to leaving town in the morning, were wearing avy gear, and were very fortunate that this ended up the way it did. 

    A clear reminder that this can happen to any of us and to be careful out there."

    Photo: Anonymous 

  • Snowmobiler triggered avalanche near Reas Peak on Sunday, 1/19/20. He was able to ride through it uphill. Photo: R. Gravatt

  • Snowmobiler triggered avalanche near Reas Peak on Sunday, 1/19/20. He was able to ride through it uphill. Photo: R. Gravatt

  • From obs: "I was on the west side of Pioneer Mtn digging a pit for YC Ski Patrol. I heard a few groups of snowmobiles cruising around the foothills of cedar. I turned and saw two snowmobilers cresting the ridge above the slide pictured as the debris was settling down. The sledders enjoyed the view for a few minutes before turning back the way they came and stumbled upon the slide they had unknowingly triggered. They skirted around the side of the crown and stopped for a few minutes. Based on the height of the rider off his sled, I would estimate the crown to be roughly 10’ at its max height. NE aspect below Cedar" Photo: J. Marcinko

  • With only 3" of new snow overnight, a cornice triggered a large avalanche at Lionhead early this morning. It broke 3 to 4 feet deep and propagated on a buried weak layer. This is the only stability test we need today, human triggered avalanches possible and the management strategy is to avoid steep slopes or be clear about your risk tolerance if you are poking into avalanche terrain. Photo: GNFAC

  • The snowpack in Lionhead is a respectable 6' deep. The facets near the ground are gaining strength and we were unable to get them to break in our tests. Stability is improving! Photo: GNFAC

  • We visited the avalanche that was triggered by a snowmobiler and partially buried 2 people on January 4th. The crown was 10 feet at the deepest part. Photo: GNFAC

  • We visited the avalanche that was triggered by a snowmobiler and partially buried 2 people on January 4th. The crown was 10 feet at the deepest part. Photo: GNFAC

  •  @carter.olson

  • From one of the riders that was caught, "The 3 persons involved were traveling across the slope about 20-30 yards up from the tree line parallel to the ridge line in the slide area when it broke, not high marking and not traveling uphill. One rider did increase his elevation while traveling across the slope but was never more than 1/4 of the way up when the slide was triggered."

  • A party of three skiers remote triggered avalanche with at least 6' crown off N face of Mt Porphry along rockband near summit on 12/29/19. They triggered it after tyhey had found "Three pits dug on NE face ascending Mt Porphry indicating increasing stability and no clean propagation. Approx 150-210 cm deep snowpack." Photo: G. Alsentzer

  • A natural avalanche observed on 12/26 from Lionhead Ridge. This slide likely broke during the storm on Christmas Eve. The avalanche is approximately 100 ft wide and on an east facing slope. It appears to have broken on a weak layer mid-pack.

    Photo: GNFAC

  • We dug this snowpit in Denny Creek at the base of Lionhead Ridge near West Yellowstone on 12/22. An poor snowpack structure makes large avalanches possible to trigger. Photo: GNFAC

  • We toured up to about 7700 feet on a NE facing aspect in the N Madison, upon entering the bottom of the meadow we had several large collapses and then one very large collapse that propagated 100+ feet uphill while on lower angle terrain below the steeper terrain Of the meadow above. We dug a pit, we got an ECTP 10. The pit was 75 cm deep, we found basal facets with an ice crust on top and About 40cm of denser 3-4 finger snow above the ice crust. Photo: A. Palombo

  • Riders saw these recent slides on 12/15 near Carrot Basin. Photo: A. Wheeler

  • Riders saw these recent slides on 12/15 near Carrot Basin. Photo: A. Wheeler

  • Riders saw these recent slides on 12/15 near Carrot Basin. Photo: A. Wheeler

  • An old avalanche crown on Lionhead Ridge, taken 12/14. Photo: G. Antonioli

  • Skiers at Targhee Pass near West Yellowstone reported: "We got a few good collapses while skinning up through east-facing low angle meadows, and got some serious cracking and collapsing while stomping on fresh wind pillows just below ridgeline on a northeast-facing slope at about 8200'. We dug down at one of the cracks and found a 35cm thick F+ slab that had failed on a layer of 4-6mm depth hoar. Cracks propagated close to 100'..." Photo: A. Schauer

  • Riders reported multiple natural slab avalanches on N facing slopes. Note widespread crowns along slope in background. Photo: R. Rustigian

  • A snowmobiler triggered an avalanche (yellow pin) north of Crown Butte (the gray mountain at the top of the image). This zone is typically approached from Lulu Pass. His sled was partially buried, but the rider was not. Lots of new snow in the last 24 hours created a CONSIDERABLE avalanche danger.

  • This natural avalanche on the northeast side of Crown Butte near Daisy Pass (Cooke City) almost caught people below. Approximately 2 feet of snow has fallen with wind and the avalanche danger is rated CONSIDERABLE. Photo: B. Whittle

Weather Forecast- Centennial Range

Extended Forecast for

10 Miles ESE Lakeview MT

  • Tonight

    Tonight: Mostly clear, with a low around 7. Wind chill values as low as -5. South wind around 10 mph.

    Mostly Clear

    Low: 7 °F

  • Saturday

    Saturday: Sunny, with a high near 28. Wind chill values as low as -5. South wind around 8 mph.

    Sunny

    High: 28 °F

  • Saturday
    Night

    Saturday Night: Mostly clear, with a low around 8. Wind chill values as low as zero. East southeast wind 6 to 8 mph becoming north northeast in the evening.

    Mostly Clear

    Low: 8 °F

  • Sunday

    Sunday: A 20 percent chance of snow after 11am.  Increasing clouds, with a high near 27. Wind chill values as low as zero. West wind 7 to 11 mph becoming south southwest in the morning. Winds could gust as high as 21 mph.

    Slight Chance
    Snow

    High: 27 °F

  • Sunday
    Night

    Sunday Night: Snow likely.  Mostly cloudy, with a low around 13. South wind around 15 mph becoming west in the evening. Winds could gust as high as 22 mph.  Chance of precipitation is 70%. New snow accumulation of less than a half inch possible.

    Snow Likely

    Low: 13 °F

  • Monday

    Monday: Snow likely, mainly after 11am.  Mostly cloudy, with a high near 21. West northwest wind 13 to 17 mph, with gusts as high as 28 mph.  Chance of precipitation is 60%. New snow accumulation of less than a half inch possible.

    Snow Likely

    High: 21 °F

  • Monday
    Night

    Monday Night: A 40 percent chance of snow.  Mostly cloudy, with a low around 6. Northwest wind around 16 mph, with gusts as high as 29 mph.  Little or no snow accumulation expected.

    Chance Snow

    Low: 6 °F

  • Tuesday

    Tuesday: A chance of snow.  Mostly sunny, with a high near 20. West northwest wind around 11 mph, with gusts as high as 18 mph.

    Chance Snow

    High: 20 °F

  • Tuesday
    Night

    Tuesday Night: Partly cloudy, with a low around 5.

    Partly Cloudy

    Low: 5 °F

The Last Word

Last Saturday, three motorized snowbikers were caught in an avalanche in Colorado and two were killed. We are deeply saddened by this accident. You can read the preliminary accident report here. Please take the time to learn what we can from this and all accidents. Stay safe if you are getting into the mountains today.