Photos

Photo: A. Bertolino

A rider triggered and was caught in this slide on 12/14. From e-mail: "...Rider was approaching blind roll over from the top when slide was triggered at the visible crown.  Rider attempted to bail, but both the individual and machine were carried over and through the rocks and strainers below.  Rider and machine were deposited in the debris pile as seen in pictures.  Rider was unharmed.  Machine was pretty well trashed...." Photo: A. Bertolino

A rider triggered and was caught in this slide on 12/14. From e-mail: "...Rider was approaching blind roll over from the top when slide was triggered at the visible crown.  Rider attempted to bail, but both the individual and machine were carried over and through the rocks and strainers below.  Rider and machine were deposited in the debris pile as seen in pictures.  Rider was unharmed.  Machine was pretty well trashed...." Photo: A. Bertolino

A rider triggered and was caught in this slide on 12/14 near Cooke City. From e-mail: "...Rider was approaching blind roll over from the top when slide was triggered at the visible crown.  Rider attempted to bail, but both the individual and machine were carried over and through the rocks and strainers below.  Rider and machine were deposited in the debris pile as seen in pictures.  Rider was unharmed.  Machine was pretty well trashed...." Photo: A. Bertolino

Skiers saw this natural crown far up Republic Creek south of Cooke City on 12/14. Photo: B. Zavora

From IG post: "Pictures don’t do this monster avalanche justice. We helped the kid recover his sled, which was buried between 4and 10 feet. luckily it wasn’t him and no one was hurt." @mackleymtvet

From IG post: "Pictures don’t do this monster avalanche justice. We helped the kid recover his sled, which was buried between 4and 10 feet. luckily it wasn’t him and no one was hurt." @mackleymtvet

From email: "Saw 3 different slides today, all had sled tracks near or into them, and were breaking from rocks.... The other slides were smaller, had broken from rocks at the top of ridges.... Crown butte, SE facing" Photo: S. Strenge

 

Riders triggered this avalanche from flat terrain nearby on Friday (12/13). Recent snow has created unstable conditions, and this is evidence that instability may persist for a while.

Outside Cooke City we dug this pit at 9800 feet on Scotch Bonnet (Dec 9). It broke on a layer of facets that formed a few days before Thanksgiving and is now buried under 1.5' of snow. The recent storm made this layer reactive. Photo: GNFAC

This avalanche on Crown Butte outside Cooke City occurred naturally on Dec 8. It is a NE facing slope above Daisy Pass. This slope is heavily wind-loaded. Photo: GNFAC

This south-facing slope on Scotch Bonnet, outside Cooke City, naturally avalanched on Dec 8. It is a wind-loaded slope and may have failed on a layer of facets 2 feet below the surface. Photo: GNFAC

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

From an email:

"Chris and I toured up the East Ridge of Mineral today and dug a pit on a NE aspect around 9000'. HS 75 cm, mostly facets with the exception of the new snow. ECTX. We found more of a windslab on some more exposed features although it wasn't reactive for us and we saw no natural avalanches with the exception of a small slide in the couloir skier's left of the summit of Meridian. We were still a ways away but it appeared to have run on the old/new snow interface." Photo: Henry Coppolillo

These small crowns indicate that new snow may not bond well to the old snow surface. Photo: B. Fredlund

This snowpit was on a NE aspect at 10,000' on Henderson Bench. It was 3 feet deep and stable. Facets (weaker snow) are getting stronger. We will keep an eye on these to make sure the positive trend continues. Our snowpit profile is here. Photo: GNFAC

This 2-foot deep snowpit consisted of layers of crusts and facets. It was dug on a SW aspect at 9800' in Miller Drainage. Nothing broke clean in our stability tests and we are optimistic about it handling a load of new snow. Photo: GNFAC

Snowpit profile is here.

We dug two pits, one on a SW aspect in the Rasta Chute off Scotch Bonnet Peak (marked with arrow) and another low on Fisher Peak at a spot called Wade's World (where Dave is standing). Photo: GNFAC

Both snowpit profiles are here.

Dave Zinn dug a pit near the top of Rasta Chute (SW aspect) near Lulu Pass and found 65 cm of snow. The layers were crusts and some facets and we determined the slope to be stable. You can look at the snowpit profile here. Photo: GNFAC