Northern Gallatin

We dropped in off the summit and my partner watched me from the top of the first cliff band while I dug below. HS 125cm. I got CT13, Q1 one foot under the surface which coincided with the natural wind slab avalanche from a few days ago. A CT16, Q1 failed one foot under that and a CT19, Q1 broke on the facets/depth hoar about one foot off the ground. Facets were F+ to 4F-. Slabs were 1F to P hardness. I was not happy about it the snow structure or test results. I decided to skin and boot back up to my partner and then head to the ridge. A big load an it’ll avalanche at the ground. It’s not great out there and the bigness of the terrain certainly increased my concern and effected my decision making, as it should. 

Jan 3, 2023: Dug a pit and found weak and unstable snow. We backtracked to the ridge. A recent avalanche from 2 days ago involved new, windblown snow. 

Did two extended column tests on the east-facing slope of Little Ellis, both pits being ~20 ft down from the summit. The snow surface was a layer of surface hoar on top of ~12 cm of new snow. Slope angle was roughly 23 degrees and each pit was 75 cm deep.

We were looking for this season's problematic and persistent weak layers in the snowpack and found them quickly. Our first pit produced an ECTP10 and pulled out all the way to the ground (the entire 75 cm slab propagated on top of a sugary layer of snow at the ground-bed surface). We decided to dig a second pit on the same slope to test again and got different but still unstable results. Our second pit produced an ECTP14 on a layer of sugary snow 30-40 cm deep, and then ECTN on the remaining column of snow (potentially due to a varying ground-bed layer of snow between the two pits – most of the snow beneath the fracture in the second pit was just sugar).

We chose to ski the ridge back to the Mount Ellis parking lot for lower-angle turns (which was our plan before digging the pit, but reinforced by our results).

Went up to Flanders today, dug a pit at approximately 9800ft on an east aspect. Snow depth was 154cm, with about 20cm of weak snow at the ground. We also found a weak layer at 112cm, which had a planar fracture during our shovel shear. Had an ECTx result, and when prying the column it pulled out as a cohesive block all the way to the ground. There was also quite a bit of surface hoar growth from about 7200ft to just below the summit.

We skied multile aspects off of the East Fork Divide. Peformed an ECT at 9,000' on a N facing slope with no results. Snowpack was 120cm. We didn't see any natural slides either. 

On both aspects, the wind / sun crust buried under the last little storm is supportable but not adhering well to that storm (some little slabs had come off people's turns about 2/3 the way down the back side) and there was ~ 1/4" surface hoar formed in the sunny spots of both aspects already at about noon today.

Natural avalanche on 1/1/23 on Saddle Peak. Appeared to involve the new, wind-drifted snow. Photo: BBSP

We looked at the avalanche that killed a snowmobiler yesterday (12/31/22) on Crown Butte near Cooke City. Our deepest condolences go out to the family and friends of the victim, and those involved with the rescue and recovery. Photo: GNFAC