18-19

From e-mail: "At Hyalite Lake we looked to our right at a slope (east facing?) and there was an avalanche that probably released 2 to 4 days ago. Probably 1 to 1.5 ft crown. Didn’t run far.... dug up above the lake. ECTN 22 about 40 cm down. Wind slab and new snow on small facets." Photo: K. Birkeland

Northern Gallatin, 2019-01-05

Slab avalanche near Hyalite Lake

Hyalite - main fork
Northern Gallatin
Code
N
Aspect
E
Latitude
45.39110
Longitude
-110.95300
Notes

Skiers saw an avalanche that released shortly after the New Year's storm cycle. From the email: "Snow was good below tree line and was nuked by the wind above tree line. Lots of variability. At Hyalite Lake we looked to our right at a slope (east facing?) and there was an avalanche that probably released 2 to 4 days ago.  See attached photo. Probably 1 to 1.5 ft crown. Didn’t run far. We kept our slope angles less than 30 degrees and dug up above the lake. ECTN 22 about 40 cm down. Wind slab and new snow on small facets." Photo: K. Birkeland

Number of slides
1
Number caught
0
Number buried
0
Number killed
0
Trigger
Natural trigger
Problem Type
Wind-Drifted Snow
Slab Thickness
18.0 inches
Weak Layer Grain type
Faceted Crystals
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

We rode into Cabin Creek behind Sage Peak (via Taylor Fork) and found 2.5' of snow. The lower half was weak, sugary and unsupportive. The upper half was a slab of recent snow that collapsed with moderate force (ECTP 11). Our sled's tracks easily broke through 2.5' of snow to the ground, a sign of poor snowpack structure. Photo: GNFAC

Southern Madison, 2019-01-04

Multiple avalanches released on wind-loaded slopes in the Bridger Range south of Bridger Bowl. The largest propagated a few hundred feet wide on Bridger Peak. Smaller slabs released in the Pinnacles and in Argentina bowl. Photo: A. Schauer

Bridger Range, 2019-01-04

Wind Slabs in the Bridgers

Bridger Peak
Bridger Range
Code
HS-N-R3-D3-O
Aspect
E
Latitude
45.76900
Longitude
-110.94100
Notes

Multiple avalanches released on wind-loaded slopes in the Bridger Range south of Bridger Bowl. The largest propagated a few hundred feet wide on Bridger Peak. Smaller slabs released in the Pinnacles and in Argentina bowl.

Multiple Avalanches
Number of slides
3
Number caught
0
Number buried
0
Number killed
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
R size
3
D size
3
Bed Surface
O - Old snow
Problem Type
Wind-Drifted Snow
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year

Small wind slab at Bridger

Bridger Bowl
Bridger Range
Code
SS-AE-R2-D1-I
Elevation
81000
Aspect
SE
Latitude
45.80920
Longitude
-110.92800
Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
An explosive thrown or placed on or under the snow surface by hand
R size
2
D size
1
Bed Surface
I - Interface between new and old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
9.0 inches
Vertical Fall
300ft
Slab Width
30.00ft
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Older crowns in Hyalite near A Lowe Peak

Alex Lowe Peak
Northern Gallatin
Code
SS-N-R2-D2
Elevation
9300
Aspect Range
N-NW-SW
Latitude
45.43390
Longitude
-110.99500
Notes

From email on 1/3/19: "On [January] 2nd, there were 4 older natural avalanches on N slopes in the Alowe basin as well as 1 recent avalanche below the NW couloir. I've attached a pic of an older slide on the SW aspect of elephant. I also got some collapsing as I skinned up the south side of the bmor/elephant saddle on the 3rd."

Multiple Avalanches
Number of slides
5
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Multiple Avalanches
Advisory Year