Northern Gallatin

Small storm slabs on Sourdough Canyon road cuts

Sourdough Canyon
Northern Gallatin
Code
SS-N-R1-D1
Elevation
6000
Aspect Range
W-NW
Latitude
45.56860
Longitude
-111.00900
Notes

We observed a few small crowns on steeper road cuts in Sourdough today, NW and W aspects. 4-8" at crown, 20-40' wide, ~10' vertical. They looked like storm slabs that had run overnight, maybe on a density change in the storm snow. Debris piles were small and covered with 2-3" of new snow. Low consequence, but maybe enough to surprise a kid or a dog. Photos were taken shortly above the 2 mile marker.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
R size
1
D size
1
Problem Type
New Snow
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

We observed a few small crowns on steeper road cuts in Sourdough today, NW and W aspects. 4-8" at crown, 20-40' wide, ~10' vertical. They looked like storm slabs that had run overnight, maybe on a density change in the storm snow. Debris piles were small and covered with 2-3" of new snow. Low consequence, but maybe enough to surprise a kid or a dog. Photos were taken shortly above the 2 mile marker.

Northern Gallatin, 2023-02-15

Small remote trigger on history rock

History Rock
Northern Gallatin
Code
SS-ASu-R1-D1
Latitude
45.48920
Longitude
-111.00500
Notes

Was about 80% of the way up to the top of the middle meadow on history rock this morning when we remotely triggered a small avalanche from the skin trackSlide was just new snow that had fallen within prior 24hrs.  Crown of about 8 inches, 20ish feet wide by 20 feet long.  Face that slid was east facing.  We took this as a sign to reconsider skiing something even as low key as history rock and decided to ski the skin track back.

[Dropped the pin for this observation exactly where I believe the observation to have occurred.  Took an OnX waypoint while out there to help too.]

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Skier
Trigger Modifier
u-An unintentional release
R size
1
D size
1
Problem Type
New Snow
Snow Observation Source
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Was about 80% of the way up to the top of the middle meadow on history rock this morning when we remotely triggered a small avalanche from the skin track.  Slide was just new snow that had fallen within prior 24hrs.  Crown of about 8 inches, 20ish feet wide by 20 feet long.  Face that slid was east facing.  We took this as a sign to reconsider skiing something even as low key as history rock and decided to ski the skin track back.

[Dropped the pin for this observation exactly where I believe the observation to have occurred.  Took an OnX waypoint while out there to help too.]

Northern Gallatin, 2023-02-15

Small nat. avalanches in Flanders

Flanders Creek
Northern Gallatin
Code
SS-N-D1
Latitude
45.44020
Longitude
-110.93100
Notes

Went for a ski up the Flanders drainage in Hyalite today. The day was punctuated by light winds and heavy snowfall.

 

On the skin in, we noted numerous D1 storm slab avalanches about 15cm down in the new snow on many aspects and elevations. Approaching a ridgeline, we experienced a shooting crack that propagated a very small slide in slightly wind affected snow. We dug an ECT on a SE facing aspect at 9000ft. We were unable to get propagation. Snow totals appeared to be higher than forecasted, with 60cm of new snow as of about 12:30. By the time we ripped skins, the area had received an additional 10cm of snow, putting totals around 60-70cm of low density snow on top of a stout melt freeze crust on the aspect we were skiing.
 

we did not observe any cracking collapsing or wumphing in buried weak layers, nor signs of avalanches on those layers. The new snow had very low SWE.

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Natural trigger
D size
1
Problem Type
New Snow
Snow Observation Source
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year

Small storm slabs on Sourdough Canyon road cuts

Date
Activity
Skiing

We observed a few small crowns on steeper road cuts in Sourdough today, NW and W aspects. 4-8" at crown, 20-40' wide, ~10' vertical. They looked like storm slabs that had run overnight, maybe on a density change in the storm snow. Debris piles were small and covered with 2-3" of new snow. Low consequence, but maybe enough to surprise a kid or a dog. Photos were taken shortly above the 2 mile marker.

Region
Northern Gallatin
Location (from list)
Sourdough Canyon
Observer Name
R. Palomaki

Small remote trigger on history rock

Date
Activity
Skiing

Was about 80% of the way up to the top of the middle meadow on history rock this morning when we remotely triggered a small avalanche from the skin track.  Slide was just new snow that had fallen within prior 24hrs.  Crown of about 8 inches, 20ish feet wide by 20 feet long.  Face that slid was east facing.  We took this as a sign to reconsider skiing something even as low key as history rock and decided to ski the skin track back.

[Dropped the pin for this observation exactly where I believe the observation to have occurred.  Took an OnX waypoint while out there to help too.]

Region
Northern Gallatin
Location (from list)
History Rock
Observer Name
JT Abate

Lots of snow in the Northern Gallatins

Date
Activity
Skiing

Went for a ski up the Flanders drainage in Hyalite today. The day was punctuated by light winds and heavy snowfall.

 

On the skin in, we noted numerous D1 storm slab avalanches about 15cm down in the new snow on many aspects and elevations. Approaching a ridgeline, we experienced a shooting crack that propagated a very small slide in slightly wind affected snow. We dug an ECT on a SE facing aspect at 9000ft. We were unable to get propagation. Snow totals appeared to be higher than forecasted, with 60cm of new snow as of about 12:30. By the time we ripped skins, the area had received an additional 10cm of snow, putting totals around 60-70cm of low density snow on top of a stout melt freeze crust on the aspect we were skiing.
 

we did not observe any cracking collapsing or wumphing in buried weak layers, nor signs of avalanches on those layers. The new snow had very low SWE.

Region
Northern Gallatin
Observer Name
Tristan M