Trip Planning for Cooke City Area

Rode out to Wolverine Pass on New Years Eve.  Daisy pass is a little spicy for novices still. On approach to  wolverine pass/YNP boundary we found HS 160cm on NE facing slope at 9200'.  Found 3-4mm SH in tact at 110 cm deep. Found 1-2mm FC at 60cm deep. Ectn27 at storm interface layer 60 cm deep. No results on SH layer, but many collapses during the day assumed to be on this layer.  Large D2-3 deep Slab avalanche seen on NW facing slope of Sunset Peak. Picture attached. Generally stable condions, but big avalanches on N,NE,NW facing slopes are a real concern for sure. 

We were ski touring on the SW side of Mt. Henderson today, and noticed a large (natural?) avalanche on the NE aspect of Henderson.  First observed at around 1:15pm.  It appeared to be very fresh, possibly from a remote trigger this morning.  

2 photos attached.   A NE aspect, around 10,000'.

It looked to be 4-6' deep and about 500' wide.  And it failed on snow at/ near the ground.

Photo: B Fredlund 

We were ski touring on the SW side of Mt. Henderson today, and noticed a large (natural?) avalanche on the NE aspect of Henderson.  First observed at around 1:15pm.  It appeared to be very fresh, possibly from a remote trigger this morning.  

2 photos attached.   A NE aspect, around 10,000'.

It looked to be 4-6' deep and about 500' wide.  And it failed on snow at/ near the ground.

Photo: B Fredlund

Scotch Bonnet Depth to Weak Layer 28 Dec 2024

A group on the "Rip Curl" area of Woody Ridge south of Cooke City report ECTP1 test results failing on buried weak layers. Photo: B. Henry

We ski toured in Sheep Creek today, north of Cooke City.  Of note, a thin (4mm) rime crust was forming due to the high humidity/ quasi rain.  Remarkably the rime crust skied very well.  Photo: B. Fredlund

We experienced several collapses and had propagation in multiple ECTs performed.  HS varies between 85-105cm. Photo from 9940

Photo: BMG

Photo: BMG

I saw a wide slab avalanche up on west Woody Ridge from town. It happened late on Wednesday or overnight during or after the strong winds and snowfall. Photo: GNFAC

Wind slab avalanche near Lulu Pass. Photo: GNFAC

Large persistant slab avalanche on Henderson. Photo: GNFAC

Persistant slab avalanche on Fisher that broke near the ground. Photo: GNFAC

D2 avalanche on east facing Mount Fox that appears to be on the SH layer, triggered by a cornice drop.

Photo: B Zavora  

NE facing, 10,000' Sheep Creek.

Photo: B Fredlund

 NE- N facing, 10,000' Mt. Henderson

Photo: B Fredlund 

NE- N facing, 10,000' Mt. Henderson

Photo: B Fredlund

NE- N facing, 10,000' Mt. Henderson

Photo: B Fredlund

E facing, 10,000 Mt. Henderson

Photo: B Fredlund

E facing, 10,200' Scotch Bonnet Mtn.

Photo: B Fredlund

NE facing, 9700', Miller Ridge

Photo: B Fredlund

 E facing, 9900', Bull of the Woods Pass 

Photo: B Fredlund

Natural avalanche, NE facing, 10,000, Miller Ridge

Photo: B Fredlund 

Lots of wind slabs south of Cooke today. Strong wind all day and lots of blowing snow. Photo: N Mattes

Plumes of drifting snow in the Bridger Range as strong winds blasted the mountains. Photo: GNFAC

The clouds broke briefly around noon on Tuesday in Cooke City. Two sections of the face on the Fin slid, one from the top, and one lower and to the right. Photo: N. Mattes 

Winds drifted snow below cornices and into gullies on Miller Ridge north of Cooke City. Photo: GNFAC

Winds drifted snow below cornices and along ridgelines on Henderson Mountain in Cooke City. Photo: GNFAC

From IG: On 12/15 "Storm slab broke about 200’ above us as skinning up the hallway coming from the north side on the throne." Photo: Anonymous

It broke on a convex rollover about 100 ft wide and ran about 80 ft. downslope. The crown averaged 30 inches and broke on sugary facets about 18 inches from the ground. Photo: Anonymous

It broke on a convex rollover about 100 ft wide and ran about 80 ft. downslope. The crown averaged 30 inches and broke on sugary facets about 18 inches from the ground. Photo: Anonymous

 Found preserved buried surface hoar approximately 15-20cms below the snow surface. 

Photo: Beartooth Mountain Guides 

Gusty winds transporting snow in Taylor Fork on Saturday. Triggered a 4-5 inch deep wind slab that propagated about 50 ft at the top of a north east facing slope at 9,500 ft.

Photo: JP

Photo: Anonymous

Surface hoar stripe in snowpit near Cooke. 

Photo: GNFAC

We skied near Lulu Pass and dug a pit on a northeast facing slope at 9,500'. There was 6-8" of low density new snow on top of a thick layer of surface hoar (10-16mm, photos attached). Photo: GNFAC

Noticed this natural avalanche on 12/8. East facing slope, ~9500 feet, Hayden Creek above Ripcurl area. Photo: J. Mundt

Snowpack on Henderson Bench on NE facing slope

Wet Loose avalanche at Lulu on South facing slope

Old wind slab avalanche on Henderson that likely failed on old facets near the ground after heavy wind loading. NE facing at about 10,100 ft.

1cm surf hoar at Lulu