19-20

From email: "On Tuesday,  April 7th my group noticed a slab avalanche above our route back to the parking lot. The coordinates of the slide are 44.7184217, -111.3190452. There were snowmobile tracks directly to the right (NW) of the slide. The slide was considerably wide , more than100 yards." Photo: H. Marcussirounian

Lionhead Range, 2020-04-09

From email: "On Tuesday,  April 7th my group noticed a slab avalanche above our route back to the parking lot. The coordinates of the slide are 44.7184217, -111.3190452. There were snowmobile tracks directly to the right (NW) of the slide. The slide was considerably wide , more than100 yards." Photo: H. Marcussirounian

Lionhead Range, 2020-04-09

Natural avalanche in Mirror Basin

Beehive Peak
Northern Madison
Code
HS-N-R2-D2-O
Elevation
10200
Aspect
N
Latitude
45.35390
Longitude
-111.40500
Notes

From obs (4/8/20): "My partner and I noticed this slide as we summited 10602 at approximately 10:30am, which is when I took the first photo and was able to capture the full runout. After our descent of the peak, we skinned back up to the slide to get a better look (the second photo). The slide appeared approximately a day old, with a crown 1-2 feet deep, on an almost directly north-facing aspect at 10200" elevation. It broke right along the rocks that had heated up in the sun, and was around 200-300 feet at its widest. We did not get close enough to determine which layer failed (suspected wind from the heavy wind-crust in the neighboring area), but the debris at the bottom indicated it was a wet slide."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Bed Surface
O - Old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
18.0 inches
Vertical Fall
600ft
Slab Width
200.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

From obs (4/8/20): "My partner and I noticed this slide as we summited 10602 at approximately 10:30am, which is when I took the first photo and was able to capture the full runout. After our descent of the peak, we skinned back up to the slide to get a better look (the second photo). The slide appeared approximately a day old, with a crown 1-2 feet deep, on an almost directly north-facing aspect at 10200" elevation. It broke right along the rocks that had heated up in the sun, and was around 200-300 feet at its widest.

Northern Madison, 2020-04-09

Natural small point release hit skier

Republic Creek
Cooke City
Code
L-N-R1-D1-S
Elevation
9000
Aspect
SE
Latitude
44.98550
Longitude
-109.94100
Notes

From obs. 4/6/20: "I got tagged by a small point release today. Skinning up the Republic Mountain ridgeline I had stopped to pull skins because it was apparent from hand-pit that the new snow was not bonding well with the old snow interface. I was looking down slope so didn’t actually see the release, but think it was a natural point release that I just happened to be standing in the way of, at least I didn’t feel any collapse so it didn’t seem like I had remotely triggered it.  

Restricted to new snow ~ 6” deep and ran for about 80 vertical feet. Point release in rock band at  ~8,980 to toe at where I was standing at 8,900’ on ESE aspect on ~35° slope ( 45.004, -109.942).

Wx: Overcast, warm (35°+), calm, snowing heavy at time (0.6 SWE at Fisher Creek SNOTEL in 10 hr.)."

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Loose-snow avalanche
Trigger
Natural trigger
R size
1
D size
1
Bed Surface
S - Avalanche released within new snow
Slab Thickness
6.0 inches
Vertical Fall
80ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

From obs on 4/6/20: "I got tagged by a small point release today. Skinning up the Republic Mountain ridgeline I had stopped to pull skins because it was apparent from hand-pit that the new snow was not bonding well with the old snow interface. I was looking down slope so didn’t actually see the release, but think it was a natural point release that I just happened to be standing in the way of, at least I didn’t feel any collapse so it didn’t seem like I had remotely triggered it.  

Cooke City, 2020-04-07