Northern Gallatin

From 12/17: "We observed numerous recent wind slabs that released naturally in the past 24 hours on NE and E aspects with some crowns starting to get covered up throughout the day. Judging from afar, I would estimate these crowns to be 6 inches to 1.5 feet deep." Photo: Tommy S.

Obs 12/17: "Saturday afternoon on the way back into town snow was moving in the Spanish peaks. Nice light" 

From obs: 12/16: "I thought this would be interesting to share but while driving around Gallatin gateway today I noticed multiple small wind pockets that released in steep draws in the gateway foothills area." Photo: M. Gaffney

My partners and I began a tour today at Hyalite Reservoir with a plan to ski the E and N faces of Mount Blackmore, but with the mindset of keeping expectations low and moving slowly giving time for observations and discussion. 

On our way in, just off the trail in an opening in the forest at 8600' on a NW aspect with an incline of 29 deg we chose to dig a test pit mostly to see if a faceted weak layer might be present on the shady aspects we were planning to ski. The pit showed a fully right side up snowpack with the snow progressively going from F hardness new snow to 1F snow towards the ground and a depth of 110cm. The snow was not wind loaded on the surface at our pit location and our ECT yielded an ECTX and no obvious signs of instability. As we climbed towards Blackmore and subsequently ascended the NE ridge, there were occasional gusts on the ridge that were actively blowing snow. The ascent towards the Blackmore summit only presented small shooting cracks and considerable cohesiveness in the surface snow in an isolated pocket towards the summit. 

We opted to ski both the E and N faces and did not notice any instabilities while skiing the lines themselves.

Skied Mt Blackmore today. Dug a pit at 9550ft on a SE facing, 23deg, slope adjacent to the standard east ridge up-track. HS150cm. No wind effect on the surface. 

Had a CTE and CTM on density changes in the top 40cm, ECTN on the same layers.

Pulling the CT block into the pit, the bottom 100 cm was very well bonded and pulled up dirt from the ground with it.

Skied numerous laps, and did not observe any signs of instability. The skiing was excellent.

Went on a tour today with a buddy and traveled through twin falls basin as well as the maid. We skied a NW slope off of Palace Butte and found touchy conditions below the ridge line, but great skiing in the trees. We also skied the bowl of Arden peak. We observed numerous recent wind slabs that released naturally in the past 24 hours on NE and E aspects with some crowns starting to get covered up throughout the day. Judging from afar, I would estimate these crowns to be 6 inches to 1.5 feet deep. 

Skied a few laps on Ellis today, E through NE aspects

No slab avalanche activity was observed (minor sluffing on steep, cold slopes)

Got off the skin track in a few places and no whumphing or cracking

Light to moderate ridgetop winds from W and SW

Trees holding snow; no drifting/ blowing snow on Ellis 

Saw A LOT of blowing/ drifting snow toward Hyalite and the Spanish Peaks at elevations above 8000'

Average HS on Ellis summit ridge 100 cm; average ski penetration 35 cm

Dug a quick test pit on a NE aspect at ~7800' (30 deg slope)

Pit results: HS 130 cm; CT 21 BRK at 85 cm; ECTX

No signs of instability; great skiing. Yay!

Didn't see any windslabs yet on NE facing burn scar. Just like ~2ft of loose fluffy snow. Trees still have snow on them, so wind probably hasn't been that bad.

I got out for a low-angle morning lap with some good folks this morning on Little Ellis and thought I'd send along a couple quick take homes:

1. We found 6 ~ 12" of new snow on our way up (and it skied excellently)

2. We saw no obvious signs of instability (cracking, collapsing, or recent avalanches)

3. We observed no wind during our outing (630 - 830am) and found no wind affected snow

4. Temperatures seemed inverted with slightly warmer temps at ridgetop vs. cool air pooled at the trailhead

5. Dug a quick handpit at the top transition and found a supportable pencil hard crust underneath the new fallen snow with well-developed large-grained facets below that... but the quick hole was in the upper scree/rock garden... so I'd expect it to harbor more basal faceted snow.

Yesterday was a beautiful ski day on Ellis.  On the approach we experienced no signs of instability.  On top there was only light, intermittent wind with no signs of wind loading.  We did experience surface sluffs on some of the steeper terrain and these could be managed.  We crossed paths with two solo skiers.  Fun day in the mountains.