Southern Gallatin

Wet Slab in Yellowstone

Other place
Out of Advisory Area
Code
WS-N-R2-D2-O
Elevation
7500
Aspect
N
Latitude
44.64320
Longitude
-110.95400
Notes

Saw what looked like a wet slab avalanche from the road along the Madison River.  Roughly north facing slope at 7500'.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Wet slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Bed Surface
O - Old snow
Problem Type
Wet Snow
Vertical Fall
250ft
Slab Width
150.00ft
Snow Observation Source
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Wet Slab Avalanche Above Quake Lake

Quake Lake
Southern Madison
Code
WS-N-R2-D2-G
Latitude
44.85240
Longitude
-111.39200
Notes

From IG: Wet slide to the ground above Quake Lake. 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Wet slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Bed Surface
G - Ground
Problem Type
Wet Snow
Vertical Fall
300ft
Slab Width
150.00ft
Snow Observation Source
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Variable Spring Conditions in the Bridger Range

Date
Activity
Skiing

We toured down the west side of the Bridger Range on the edge of Truman Gulch and found predictably weak snow on an upper-elevation NW-facing slope. Conditions were variable and transitioned to a thick crust as we moved on to a lower elevation, west-facing slope. By the time we came down the Ramp, the snow was getting wet, we saw roller balls, and we avoided steep, sun-exposed terrain. 

We dug below NW Passage. It was a 135 cm deep snowpack, dry throughout, with Fist plus hard facets and depth hoar making up the foundation (ECTP30, PST 42/100 end at 30 cm from the ground. 

Region
Bridger Range
Location (from list)
Truman Gulch
Observer Name
Dave Zinn

Wet snow at Lionhead

Date
Activity
Snowmobiling

We rode from the Buttermilk trailhead up Denny Creek to Lionhead Ridge, along Lionhead Ridge through Watkins Creek and to the motorized boundary at the head of Targhee Creek. 

There was a ~1" crust at the surface when we left the trailhead, with dry snow beneath. We saw our first wet loose avalanche of the day running around 11 am. By 12:30 there were dozens and many rollerballs. None of them ran particularly far or picked up too much volume.  The snow surface was moist on sunny slopes by late morning, but not more than a few inches down.

We saw one small slab avalanche that occurred since this weekend's snow. It appears to have been triggered by a snowmobile yesterday (4/1/24). It broke 10" to 2 ft deep, 50 ft wide, and ran ~50 vertical feet. It broke on a thin layer of facets beneath the new snow. Digging in the crown, dry facets at the ground were along still present and weak (fist hardness).

Signs of older avalanches were visible beneath the new snow, including one slide that broke in early March. No cracking or collapsing were observed today.

Region
Lionhead Range
Location (from list)
Lionhead Ridge
Observer Name
Ian Hoyer