19-20

Natural slab near Cooke

Cooke City
Code
SS-N-R2-D2
Notes

From email (4/4/20): "...east aspect, around 9700'.  The crown looked to average about 2' deep, and it was about 400' wide. I'd estimate that this avalanche happened on April 1 or 2.  (2-3 days ago)".

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Slab Thickness
24.0 inches
Slab Width
200.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Skier triggered thin slab in Beehive

Beehive Peak
Northern Madison
Code
HS-ASu-R1-D1.5-O
Elevation
10500
Aspect
S
Latitude
45.35390
Longitude
-111.40500
Notes

From obs 4/4/20: "Avalanche, 4th of July Couloir, Beehive. No person was caught. A dog was caught but not buried. Crown between 2 and 5 inches, based on cracking depth during ascent and pictures. Runout aproximately 120x40 yards. Estimated using gaia gps.

Myself, a partner, and my dog left the busy Beehive parking lot at approximately 0945 this morning (04/04). We noted no instabilities on the approach other than a small debris field under a cornice on the east facing aspect of the ridge to the southwest of Beehive peak. Given the lack of a cornice on our intended route, and the small size of the noted avalanche, we decided to dig a pit and make our decision based on those results.

We dug our pit at the base of the bowl, right under the peak, and had no result. On our ascent, we noted some cracking, which would break on a depth of between 2 and 5 inches. We decided that we would continue, unless the cracking started breaking significantly deeper, based on the relatively light snow and mellow run out. In hindsight, this was a poor decision, especially given the dog with us. Once we got up, we briefly considered skiing the northern aspect, but decided against it based on evidence of wind grooming and the constriction on that side.

The first half of our descent was smooth, although the skiing was somewhat punchy, evidence of wind affected snow. Right after the narrowest part of the couloir I felt the snow under me start to move, but I was able to ski to the right, out of the path. Although the dog was caught, she was fortunately not buried and sustained no injuries. My partner was above me, not in line of sight, and did not know the slide had occurred until he skied down to me. The slide was witnessed by at least two other parties in Beehive."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Skier
Trigger Modifier
u-An unintentional release
R size
1
D size
1.5
Bed Surface
O - Old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
5.0 inches
Vertical Fall
400ft
Slab Width
20.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Skier triggered slab 4th of July, Beehive 3

From obs 4/4/20: "Avalanche, 4th of July Couloir, Beehive. No person was caught. A dog was caught but not buried. Crown between 2 and 5 inches, based on cracking depth during ascent and pictures. Runout aproximately 120x40 yards. Estimated using gaia gps."

Northern Madison, 2020-04-04

Skier triggered in 4th of July, Beehive 2

From obs 4/4/20: "Avalanche, 4th of July Couloir, Beehive. No person was caught. A dog was caught but not buried. Crown between 2 and 5 inches, based on cracking depth during ascent and pictures. Runout aproximately 120x40 yards. Estimated using gaia gps."

Northern Madison, 2020-04-04

Skier triggered in 4th of July couloir, Beehive

From obs 4/4/20: "Avalanche, 4th of July Couloir, Beehive. No person was caught. A dog was caught but not buried. Crown between 2 and 5 inches, based on cracking depth during ascent and pictures. Runout aproximately 120x40 yards. Estimated using gaia gps."

Northern Madison, 2020-04-04

Snowmobile triggered slab Portal Creek

Portal Creek
Northern Gallatin
Code
SS-AMu-R2-D2-O
Latitude
45.28900
Longitude
-111.14100
Notes

From obs. 4/4/20: "Avalanche today up portal creek. 2 1/2 ft crown and 4 - 5 ft runout. Triggered by snowmobile. Everyone was safe!"

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
Bed Surface
O - Old snow
Problem Type
Persistent Weak Layer
Slab Thickness
30.0 inches
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year