19-20

Skier triggered small sluffs on Little Ellis

Mt Ellis
Northern Gallatin
Code
L-ASc-R0-D1
Elevation
7450
Aspect
NE
Latitude
45.57770
Longitude
-110.95500
Notes

Winds only 5mph out of the west, temps in the 20’s, 8-10” new snow overnight. Dry-loose intentionally triggered D-1’s from ridge-top on 45 degree NE-facing slopes at 7450’. Otherwise, no obvious signs of instability, skied down through N Ridge glades.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Loose-snow avalanche
Trigger
Skier
Trigger Modifier
c-A controlled or intentional release by the indicated trigger
R size
0
D size
1
Problem Type
New Snow
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Collapsing and natural avalanches at Quake Lake

Quake Lake
Southern Madison
Code
SS-N-I
Elevation
9600
Aspect Range
E and N/NW
Latitude
44.85240
Longitude
-111.39200
Notes

"I skied near Quake Lake today, and observed several signs that the snowpack has not adjusted to this last storm yet. While ascending, several drifts collapsed under my weight, and I observed a very recent natural slide on a wind-loaded, east facing slope at about 9200'. I saw another, larger natural slide on a wind-loaded N/NW slope at 9600' that looked to have run on the new/old interface sometime late yesterday. I dug a pit on a south aspect at 9900', and found a thin layer of graupel on top of a crust 35cm down. This failed at ECTP3, which was a little hair-raising. The rest of the pack on that aspect seemed to be fairly well consolidated..."

Number of slides
2
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
Bed Surface
I - Interface between new and old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
35.0 centimeters
Weak Layer Grain type
Graupe
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year

"I skied near Quake Lake today, and observed several signs that the snowpack has not adjusted to this last storm yet. While ascending, several drifts collapsed under my weight, and I observed a very recent natural slide on a wind-loaded, east facing slope at about 9200'." Photo: Sam Reinsel

Southern Madison, 2020-04-01

Multiple signs of instability above Hebgen Lake

Hebgen Lake
Lionhead Range
Code
Aspect
E
Latitude
44.83810
Longitude
-111.34300
Notes

Today at Hebgen we were all excited obviously about the new snow.  Having heard about and seen the surface hoar that formed several weeks ago, this was definitely on my mind, but figured like usual we would mitigate our risk and stay on mellower terrain to avoid causing or being caught in a slide. As we got higher and broke out into 1 of the higher meadows we got a good woomph that stopped the three of us in our tracks. We skinned a little further and then dug a pit confirming what we were already concerned about, ectp 18. We rode from the ridge and then cut back to the skintrack along the ridge (commonly where most folks skin up) and kept out of the steeper slide paths.

4 red flags I observed, not to mention the Considerable danger rating given in the morning for S. Madison.  1) the big woomph 2) poor test results 3) riding in or near terrain traps.

Number of slides
0
Number caught
0
Number buried
0
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Red Flag
Advisory Year

Slope fractured, but did not slide on Buck Ridge

Buck Ridge
Northern Madison
Code
AM-O
Elevation
9500
Aspect
N
Latitude
45.18190
Longitude
-111.36700
Notes

"East side of first yellow mule north facing slope. Fractured above but did not slide higher."

Number of slides
0
Number caught
0
Number buried
0
Trigger
Snowmobile
Bed Surface
O - Old snow
Problem Type
New Snow
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Red Flag
Advisory Year

Skier caught in large sluff at Bridger Bowl

Bridger Bowl
Bridger Range
Code
L-ASu-R2-D2-I
Elevation
9000
Aspect
E
Latitude
45.81560
Longitude
-110.92300
Notes

An email with some edits:

This morning I skinned up to the ridge alone and went south. I made a turn into some trees and triggered a small sluff below me. I wasn’t comfortable with the amount of snow I moved, so I sidestepped up to the ridge and went back north to the Nose. I dropped into the Nose and made my way to the chute Bombs Away. I skied through Bombs Away and made a few turns in the large apron below the chute before a large sluff I triggered above caught up to me. I stayed on my feet and went through some tight trees, ripping a couple of straps off my backpack, and then I got knocked onto my back. As the slide began to slow, I popped up quickly and managed to ski away. My familiarity with Bridger when it is patrolled influenced my poor decision making, as well as a false sense of being comfortable in dangerous terrain. I am extremely lucky and grateful that it wasn’t worse. I hope others try to avoid similar, poor decision making in this strange post-season at Bridger Bowl.

Another observation from 10 am:
15" crown N facing Knob Job 1. Going on interface between Monday/ Tuesday snow. Thin line of NSF maybe. Crossing Boundary Chute that had mostly cleaned itself out on the upper section, pushed on it on the N facing side and got 2 good whoompfs.

Number of slides
1
Number caught
1
Number buried
0
Avalanche Type
Loose-snow avalanche
Trigger
Skier
Trigger Modifier
u-An unintentional release
R size
2
D size
2
Bed Surface
I - Interface between new and old snow
Problem Type
New Snow
Slab Thickness
40.0 centimeters
Slab Layer Hardness
F+
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year