Cooke City

This is avalanche weather - heavy snowfall and strong winds transporting snow. With this weather, it doesn't really matter what's going on in the snowpack. The loading from snowfall and strong winds will find the weakest layer in the snowpack and produce persistent slab avalanches.

Snow depths going up from Republic Creek at 8200 ft to the top of Woody Ridge at ~10,000 ft  ranged from 60 cm to 120 cm. Weaker where thinner and stronger where deeper. What surprised me was that we couldn't get a single collapse/whumpf or any cracking despite our best efforts getting off the established skin track. Given the rapid loading and wind loading combined with buried facets, I expected at least on collapse. However, a lack of collapsing doesn't override all the other red flags. 

The snowpack north of town and south of town seemed reasonably similiar. The biggest differences were with elevation. Generally above maybe 9000-9500 ft, the snowpack is a goof 4 feet deep. 

I WON'T BE SURPRISED TO HEAR OF SOME LARGE AVALANCHES AT UPPER ELEVATIONS on peaks like Henderson, Crown Butte, etc where some slopes are being heavily wind-loaded. 

Looking into the future, though, I feel optimistic. The snowpack is growing and will hopefully get stronger in the future as weak layers are insulated and buried more deeply. Yesterday north of Cooke, weak layers generally buried about 2 feet deep showed signs that they were gaining some strength and hardness. We'll see. 

We rode around a big chunk of the Cooke City area from the Miller Road, up to Daisy, around the backside of Fisher Mtn, into Fisher Creek, and looping around Scotch Bonnet Mtn. Ee saw no signs of instability. No cracking or collapsing. While tracks on slopes don't indicate stability, there were a lot of tracks on small test slopes, and none produced small avalanches. 

In all our snowpits, the weak layers were generally 2-2.5 feet deep and I was pleasantly surprised that they seem to be gaining some hardness. It feels that the snowpack has benefited from the steady trickle of light snow in the Cooke area. It hasn't added much water weight, but the continuous light snowfall in the Cooke Area has been slowly insulating and burying the weak layers without stressing them.

Unfortunately, we could not find any buried surface hoar, but we know it's out there. We also know that other areas like slopes south of town up Republic Creek are likely much weaker. 

Without a major load of snow (and water), below treeline, avalanches are still possible but don't feel too imminent. It's different story going above treeline - where avalanches have been happening, where there's lots of wind loading, and where there are lots of potential trigger points. Stay below treeline.

Scotch Bonnet Depth to Weak Layer 28 Dec 2024

Scotch Bonnet Profile 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

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

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