23-24

more recent avalanches in Cooke

Date
Activity
Skiing
Snowmobiling

Saw a few slides that look like they propagated across the layer of new snow from the last storm (as opposed to the characteristic spring wet snow point releases). The largest was the previously reported one from Sheep. On the way out we saw a smaller slide farther south along the same ridge that looked like it broke on the new snow interface, both NE aspects.

We also saw a similar slide on a N/NW aspect of Mt Zimmer. 
 

Hard to say from a distance when these broke, but the one on Mt Zimmer looked the most recent. 

Region
Cooke City
Location (from list)
Mt. Zimmer
Observer Name
Amanda Kautzer

Rider triggered avalanche on Fisher mtn

Fisher Mtn.
Cooke City
Code
SS-AMu-R2-D2
Elevation
10000
Aspect
E
Latitude
45.06610
Longitude
-109.95900
Notes

From email 5/11/24: “Hey Guys, here are a few photos from the weekend.... the fisher peak avalanche happened today. Maybe cornice drop?”

From email 5/16/24: "I saw the photo of the fisher peak avalanche on the website. Figured I could fill in the blanks. Not a natural slide, snowmobile triggered.

At approximately 12:15pm last Saturday I was climbing above fisher bench and unintentionally set off a slab avalanche on fisher peak. I was jumping the cornice at the ridge and had a massive slope collapse, followed by shooting cracks and propagation downslope. I was able to wheelie through the crown and sidehill above the slide away from the debris area.

5 minutes before my climb, another snowmobiler put a high mark 60 ft away from where I climbed with no results. There were numerous tracks on the slope prior to this avalanche, I found the weak spot. My riding partner was watching me from a safe zone further south, as we knew there was new snow instabilities to watch out for, at a minimum.

We rode all day Friday without any obvious instabilities on similar slopes. We didn’t see the sheep mountain slide Friday morning. I took some pictures of the slide right after it happened. See attached…"

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Snowmobile
Trigger Modifier
u-An unintentional release
R size
2
D size
2
Problem Type
New Snow
Slab Thickness
20.0 inches
Vertical Fall
350ft
Slab Width
300.00ft
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Snowmobile triggered slide on Sheep

Sheep Mountain
Cooke City
Code
SS-AMu-R3-D2
Elevation
9500
Aspect
NE
Latitude
45.07220
Longitude
-109.92800
Notes

From email 5/11/24: “Hey Guys, here are a few photos from the weekend. The sheep Mountain Avalanche was Snowmobile triggered on Friday and the fisher peak avalanche happened today. Maybe cornice drop?”

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Snowmobile
Trigger Modifier
u-An unintentional release
R size
3
D size
2
Problem Type
New Snow
Slab Thickness
24.0 inches
Vertical Fall
420ft
Slab Width
500.00ft
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Recent avalanches

Date

From email 5/11/24: “Hey Guys, here are a few photos from the weekend. The sheep Mountain Avalanche was Snowmobile triggered on Friday and the fisher peak avalanche happened today. Maybe cornice drop?”

Region
Cooke City
Location (from list)
Sheep Mountain
Observer Name
Ben Zavora

New snow instability

Date
Activity
Skiing

From IG message 5/10: "Made it most the way up Ross today turning around at the step up to the east shoulder. New snow is resting on a layer of graupel. New snow has not bonded to the old. CT12, Q2 at 90cm from the ground. HS=150cm'

Region
Bridger Range
Location (from list)
Ross Peak
Observer Name
Tyler Miller

Remote triggered storm slab near Cooke

Round Lake
Cooke City
Code
SS-AMr-R2-D1
Elevation
9000
Latitude
45.07450
Longitude
-109.90700
Notes

From IG story 5/8/24: "@mtavalanche remote triggers today in Cooke City. 2-4' of fresh north of round lake."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Snowmobile
Trigger Modifier
r-A remote avalanche released by the indicated trigger
R size
2
D size
1
Problem Type
New Snow
Slab Thickness
14.0 inches
Vertical Fall
30ft
Slab Width
42.00ft
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Remote triggered storm slabs

Date
Activity
Snowmobiling

From IG story 5/8/24: "@mtavalanche remote triggers today in Cooke City. 2-4' of fresh north of round lake."

Region
Cooke City
Location (from list)
Round Lake
Observer Name
BPG