Observation: Bonkers

Observation Date
12/10/2018
Observer Name
mark white
Region
Salt Lake » Big Cottonwood Canyon » Broads Fork » Bonkers
Location Name or Route
Bonkers, Broads Fork
Weather
Sky
Few
Wind Direction
Southwest
Wind Speed
Light
Weather Comments
The wind wasn’t blowing much down in the hole but I could see it moving snow on the Blue Ice and across the face of the Diving Board I was protected from it by one of the Twins
Snow Characteristics
Snow Surface Conditions
Powder
Faceted Loose
Wind Crust
Damp
Snow Characteristics Comments
Pretty much finding square powder or as the scientist call it faceted snow on the surface of protected NE, mixed in with wind slabs and wind crust in the higher less protected terrain. Damp snow was present on the sunny SE facing.
Red Flags
Red Flags
Poor Snowpack Structure
Comments
Went up Broads Fork to have a look at the Diving Board and Bonkers, pretty sure I was the first person up there this season on skis. The Diving Board looked wind jacked and also had not avalanched so I took that off the agenda, and decided to walk up the E-SE facing side of Bonkers and have a look. I dug two pits on the way up, one was at 92000ft E facing with a touch of S about halfway up the run, this revealed a stable snow pack with no old and weak snow, kinda what I was expecting. But farther up the slope probably about 2/3 of the way up I got in the main gut and dug a pit this pit was NE facing 9600ft where the steep upper bowls flatten out, whole different world. The pit revealed a much deeper snow pack, with a stout crust at the ground then a layer of large grain facets then the October crust which was thin but still intact with a layer of facets on top, then a fairly stout slab. Compression test failed on the facets above the crust with a fairly easy shear. It seems like the upper bowls may have avalanched at some point in time but the structure of the snow was telling me going higher into steeper terrain with no SE facing to walk up was a bad idea and I skied from there. The two pits really scream aspect, aspect, aspect, one with totally stable snow and the other one in the same vicinity with poor structure and a easy shear. The price of admission is high, not much snow until the upper basin with a lot of walking required.
photos: first snow pit on E, second snow pit on NE and 400ft higher, surface hoar, and wet activity, and a video showing the second pits location
Video
FORECASTER NOTE: Another spot-on observation from Mark White. Lots of nuance going on in respect to even slight aspect change within the same route. I bailed 2/3 way up Bonkers myself last season.
Hardesty
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate