Regional Conditions for Southern Gallatin

as of 5:00 am
Apr 302″ | N/A
Apr 29 0″ | N/A
Apr 28 1″ | N/A
9400′     04/02 at 13:00
40.6℉
E - 2mph
Gusts 14mph
8880′   07/21 at 15:00
69℉
0″ Depth
Bottom Line: Avalanches will be mostly confined to new snow that falls. Shallow wet slides are possible if rain or warm temperatures melt the snow surface. Anticipate new snow stability to decrease with wind, sun or above freezing temperatures. Be aware of deeper wet slides if the snowpack doesn’t freeze overnight, or if there is heavy rain. Now is just as important as ever to be diligent with snowpack assessment and choose terrain carefully. See our forecast page for general spring snowpack and travel advice.

Past 5 Days

Fri Apr 19

None
Mon Apr 22

None
Fri Apr 26

None
Mon Apr 29

None
Thu May 2

None

Avalanche Activity- Southern Gallatin

Photos- Southern Gallatin

Displaying 1 - 40 of 4.6116860184274E+18
  • 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

  • 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

  • Debris from an older wet loose slide observed 4/20/19. Estimated to be a week old. 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

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

  • From e-mail on 4/11/19: "We found reactive storm slabs and touchy windslabs near ridgelines. We kicked off a small windslab in 4th of July from the top of the couloir. Attached is a photo of the crown to give you a depth perspective. It was about 6 feet across and 3-4 inches deep."

  • 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

  • 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 snowmobiler saw this recent activity on Saturday 3/9/19 on Cedar Mountain near Big Sky.

  • This slide was triggered on a steep (40 deg) southeast facing slope at Round Lake outside Cooke City. It failed 8" deep on a layer of graupel and small facets. An adjacent hill slid at the same depth beforehand. This layer is not on most slopes, but as this slide shows it is on some. Doug was in the area and dug a pit in the crown soon after it was triggered. Photo: J. Fritz

  • This slide on the NE face of Blackmore was triggered by the second skier. It was 8-12" deep and 100' wide and likely failed on small faceted crystals underneath the new snow. No one was caught. Going one at a time was good travel behavior that can save our lives when things go wrong.

  • A snowmobiler triggered this slide on the afternoon of 3/2/19 behind Sage Peak in the southern Madison Range. Photo: J. Hillier

  • We received this report of an unusually large natural avalanche in the East Mill Creek drainage: " First time in 17 years we have had an avalanche come into our road. Natural, maybe from a point release that fractured new snow about 20 inches at the crown, propagated 50 yards, ran about 300 feet without stepping down, leaving about 5 foot deep debris. A new 2 inches is covering the debris that likely went during this afternoons warming."  Photo and comments: L. Watson

  • 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."

  • 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

  • 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

  • "One small slide on a N asp at head of Bacon rind creek, elev 8750,  had a crisper look than most of the others observed, suspect more recent." Photo: M. Best

  • 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).

  • 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.

  • 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 

  • We rode into Cabin Creek behind Sage Peak (via Taylor Fork) and found 2.5' of snow. The lower half was weak, sugary and unsupportive. The upper half was a slab of recent snow that collapsed with moderate force (ECTP 11). Our sled's tracks easily broke through 2.5' of snow to the ground, a sign of poor snowpack structure. Photo: GNFAC

  • Snow bikers in the northern Gallatin Range "witnessed a very reactive new snow layer in all wind loaded areas." (12/30). Photo: J. Polus

  • 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

  • A skier reported a recent slab avalanche at Ernest Miller in the southern Madison. This is a good reminder that as you move further south in our advisory area, we are seeing a thinner and generally less stable snowpack. Photo: C. Grote

  • A skier in the southern Gallatin found a buried layer of surface hoar that propagated in stability tests. This surface hoar layer has been found at several locations in the advisory area. Photo: S. Reinsel

Videos- Southern Gallatin

Weather Forecast Southern Gallatin

Extended Forecast for

17 Miles SE Big Sky MT

  • Tonight

    Tonight: Mostly clear, with a low around 47. North northeast wind 5 to 7 mph becoming light and variable  in the evening.

    Mostly Clear

    Low: 47 °F

  • Monday

    Monday: Isolated showers and thunderstorms after noon.  Sunny, with a high near 78. Light and variable wind becoming southwest 5 to 7 mph in the morning.  Chance of precipitation is 20%.

    Sunny then
    Isolated
    T-storms

    High: 78 °F

  • Monday
    Night

    Monday Night: A slight chance of showers and thunderstorms before 9pm, then a slight chance of showers between 9pm and midnight.  Mostly clear during the early evening, then becoming cloudy, with a low around 55. Northeast wind around 7 mph becoming south after midnight.  Chance of precipitation is 20%.

    Slight Chance
    T-storms then
    Partly Cloudy

    Low: 55 °F

  • Tuesday

    Tuesday: A 40 percent chance of showers and thunderstorms after noon.  Partly sunny, with a high near 80. Southeast wind 5 to 9 mph becoming west southwest in the afternoon.

    Mostly Sunny
    then Chance
    T-storms

    High: 80 °F

  • Tuesday
    Night

    Tuesday Night: A 20 percent chance of showers and thunderstorms before midnight.  Mostly cloudy, with a low around 55. West southwest wind 5 to 7 mph becoming light and variable.

    Slight Chance
    T-storms then
    Partly Cloudy

    Low: 55 °F

  • Wednesday

    Wednesday: A 40 percent chance of showers and thunderstorms, mainly after noon.  Mostly sunny, with a high near 75. Breezy, with a south wind 6 to 15 mph becoming west in the afternoon. Winds could gust as high as 28 mph.

    Chance
    T-storms and
    Breezy

    High: 75 °F

  • Wednesday
    Night

    Wednesday Night: A 20 percent chance of showers and thunderstorms before midnight.  Mostly clear, with a low around 48. West wind 5 to 8 mph becoming north after midnight. Winds could gust as high as 24 mph.

    Slight Chance
    T-storms then
    Mostly Clear

    Low: 48 °F

  • Thursday

    Thursday: Sunny, with a high near 74.

    Sunny

    High: 74 °F

  • Thursday
    Night

    Thursday Night: Mostly clear, with a low around 49.

    Mostly Clear

    Low: 49 °F

The Last Word

Have a safe and enjoyable spring and summer. See you when the flakes start to fly next Fall! -Doug, Eric, Alex and Ian