Small, cornice triggered avalanche, Beehive

Beehive Basin
Northern Madison
Code
SS-NC-R0-D1-O
Elevation
9000
Aspect
E
Latitude
45.32570
Longitude
-111.38000
Notes

Today we toured up Beehive Basin to Prayer Flags and down into Bear Basin. We found moderate winds transporting snow at Prayer Flags. We also observed a recent small natural avalanche that broke just below the cornice at prayer flags (9200'). It was unclear if a cornice collapse triggered the avalanche. We did not go to the crown, but estimated it to be about 20-30 feet wide, 6-8 inches deep, and running less than 100 feet (Photo attached).

During our tour we saw lots of pillows of wind drifted snow and locations where slabs of wind drifted snow collapsed and cracked under our skis. 

In Bear Basin we dug a pit and found weak faceted snow on the ground. We did not have any significant test results, but the structure along with the wind and recent avalanche activity was enough to keep us off steep slopes for the day. 

The snow surface was powder in protected places, breakable wind crust in others, and either scoured or wind board at ridge lines.The skiing was best on low angle slopes protected from the wind. 

Number of slides
1
Number caught
0
Number buried
0
Avalanche Type
Soft slab avalanche
Trigger
Cornice fall
R size
0
D size
1
Bed Surface
O - Old snow
Problem Type
Wind-Drifted Snow
Slab Thickness
6.0 inches
Vertical Fall
100ft
Slab Width
30.00ft
Snow Observation Source
Slab Thickness units
inches
Single / Multiple / Red Flag
Single Avalanche
Advisory Year