23-24

We toured up to Flanders Mtn and saw a big, deep 2-6' deep avalanche that broke 300-500' wide in weak snow at the bottom of the snowpack. It broke across two separate start zones and included a lower angle ridge (still around 30 degrees) in between that slid. E-NE aspect at 9,800'. HS-N-R3-D3-O.  Photo: GNFAC

 

Northern Gallatin, 2024-03-30

We toured up to Flanders Mtn and saw a big, deep 2-6' deep avalanche that broke 300-500' wide in weak snow at the bottom of the snowpack. It broke across two separate start zones and included a lower angle ridge (still around 30 degrees) in between that slid. E-NE aspect at 9,800'. HS-N-R3-D3-O.  Photo: GNFAC

 

 

Northern Gallatin, 2024-03-30

Natural deep slab avalanche

Date

We toured up to Flanders Mtn. to take down the weather station for the season (before the road closes on Monday, Apr 1). The main observation is a big, deep 2-6' deep avalanche that broke 300-500' wide in weak snow at the bottom of the snowpack. Photos and video attached. It broke across two separate start zones and included a lower angle ridge (still around 30 degrees) in between that slid. E-NE aspect at 9,800'. HS-N-R3-D3-O. 

Next to the avalanche debris there was 1-2" of new snow on a thin melt-freeze crust, and the debris seemed to have around 3" of new snow on it. Minimal evidence of recent wind.There was a trace of new snow in the parking lot, 3-6" on most of the trail, I think from the last couple days, and places up high had 10-12" of recent snow where the sun hadn't affected snow from earlier in the week. Today wind was calm with sunny skies becoming partially obscured with light snow showers. We also saw one small dry loose slide in the new snow on a steep north facing slope, and a variety of older crowns including wind slabs near the ridge and one 2-3' deep crown below some cliffs.

 

Region
Northern Gallatin
Location (from list)
Flanders Creek
Observer Name
Alex Marienthal

Beehive basin pits

Date
Activity
Skiing

Today, myself and 5 others toured up beehive basin for an avalanche 2 course. In the morning a pit was dug in the bonus wiggles on a south facing slope. The biggest takeaway from this was the melt freeze crust on the surface. This pit experienced an ECTP-22 and CT-15-Q1. Both tests failed on depth hoar 40 cm above the ground. Another pit was dug on an east facing slope on the west side of beehive basin in an opening between tree fields, about 30ft from the ridge line. The biggest takeaways from this pit where a PST 40/120-end at the surface hoar-melt freeze crust interface 40cm above the ground and ECTN on the upper crust. As for the surface, the surface crust softened for the afternoon decent. There was little to no wind today and no evidence of wind slab, no observed avalanches, and no observed cracking or collapsing. 

Region
Northern Madison
Location (from list)
Beehive Basin

Test Pit Observations in Beehive

Date
Activity
Skiing
Snowboarding

Our group conducted an East facing snow pit on the top of the East Beehive Ridge at around 9100’, at 1 pm. Sky was OVC, wind from W at 5 mph. Snow pit was on a 15° slope.  The total snow depth was 135 cm. Our results were an ECTN 22 at 35 cm down, a PST 34/100 End and 85 cm down, and a DT 21 PC at 100 cm down. No observed wind slabs on ridge south of Prayer Flag Trees. No signs of wet loose such as rollerballs at 4 pm. 

Region
Northern Madison
Location (from list)
Beehive Basin
Observer Name
MSU AVY 2 Class

Poor test scores on bacon rind

Date
Activity
Skiing

Dug a pit near the top of bacon rind on an east facing slope. ECT-P 14 on the new snow slab breaking 12” deep 

Region
Southern Madison
Location (from list)
Bacon Rind

2 slides in Upper A-Zs

Date
Activity
Skiing

Saw 2 small avalanches running down the upper A-Zs when I was standing at the top of the Gullies at 10:44am. No ski patrollers in sight. I got a video of them moving but didn’t catch the start. Sun was directly hitting the ridge at the time. 

Region
Northern Madison
Location (from list)
Big Sky Resort