A skier in Hyalite found a buried layer of near surface facets (NSF) that was reactive in stability tests and responsible for several avalanches in the Hyalite Peak area. He described this buried weak layer in an email: "It is currently down anywhere from 10-40 cms, above treeline, primarily on W-N-E aspects (not on S, there is a crust). I was hoping that yesterday’s warm temps may have helped, but things felt funky underfoot, and I got an ECTP13 (E aspect, 33 deg, 9900 ft), and bailed on my primary objective. I also observed several natural avalanches (HS-N-D2R2-I) that appeared to have failed on this layer a couple days ago, on Wind loaded N aspects above 10k. Besides this, there were no other signs of instability, no shooting cracks etc."
Hyalite Peak
Northern Gallatin
Code
HS-N-R2-D2-I
Elevation
10000
Aspect
N
Aspect Range
W, N, E
Latitude
45.38090
Longitude
-110.96100
Notes
Number caught
0
Number buried
0
Number killed
0
Avalanche Type
Hard slab avalanche
Trigger
Natural trigger
R size
2
D size
2
Bed Surface
I - Interface between new and old snow
Problem Type
Wind-Drifted Snow
Slab Thickness units
centimeters
Single / Multiple / Red Flag
Single Avalanche
Advisory Year