Date of Observation: 03/18/2023
Name: Evan Ross

Zone: Northwest Mountains
Route Description: Slate River

Observed avalanche activity: Yes

Snowpack: Loose-dry and Loose wet avalanches looked like the primary avalanche problems NTL and BTL. Both natural and skier-triggered. Most of the wet avalanche activity appeared to have occurred yesterday or previously. I didn’t travel on southerly-facing slopes today and don’t know how wet they got, but temperatures did feel cooler than yesterday. The only recent slab avalanche I saw was in the Great Wide Open of Skooks. It looked like it failed after yesterday morning’s 1″ of fairy dust.

Date of Observation: 03/18/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: Traveled on all aspects of Mt. CB to 11,800 to observe current snow surfaces ahead of the next storm.

Observed avalanche activity: Yes
Avalanches: Had good views with binoculars of a lot of terrain. Nothing notable from the past few days; some small loose avalanches and recent cornice fall/wind slab activity off of Owen that looked to be about D1.5 in size.
Weather: Notable 30-degree diurnal swing at Butte SNOTEL past 36 hours with temps dropping to near zero overnight, and highs near freezing. Light winds, clear skies.
Snowpack: The current snow surface is the most widespread and notable near-surface faceting event I’ve observed this spring, which will spell trouble for the upcoming storm. The combination of low-density snow at the tail of the last storm, light winds, and big temperature swings the last few days have promoted faceting in the upper few cm’s of the snowpack. Today’s cool temps and strong March solar were ideal for radiation recrystallization. I found 1cm of dry, faceting grains above thin crusts (1 to 3 cm) on east, south, and west aspects, grain sizes about 1mm in size. Northerly aspects held cohesionless facets, ~1mm. I suspect only the lowest elevation southerlies got warm enough to cook off, but I didn’t verify that.

Date of Observation: 03/17/2023
Name: Chris Martin

Zone: Southeast Mountains
Route Description: Aspen to CB via Starr Pass. We traveled over the pass via wind scoured ribs and ridges Wednesday morning before the intense precip of another river Wednesday evening.

We awoke thursday evening to the most quality powder skiing i’ve ever experienced in the friends hut zone.

Observed avalanche activity: Yes
Avalanches: Carbonate Hill Flank SE – D2 R2 Hard Slab – Natural – failing at the ground, seemingly sometime Wednesday evening

Many various shallow storm slabs failing on solar crusts about 4-12″ in thickness
Weather: Heavy precip Wednesday PM along with howling winds
Clear sunny skies Thursday
Snowpack:

Date of Observation: 03/17/2023
Name: Zach Guy

Date of Observation: 03/17/2023
Name: Frank Stern

Zone: Southeast Mountains
Route Description: Wolverine Basin

Observed avalanche activity: Yes
Avalanches: N facing slope 12,000’
Weather: Sunny
Snowpack: Powder on N aspects, crust on S

Date of Observation: 03/17/2023
Name: Travis Guy

Zone: Southeast Mountains
Route Description: Gothic townsite to Kettle Ponds

Observed avalanche activity: Yes
Avalanches: 3 avalanches that had already run on 2nd bowl. Appeared to be natural as I couldn’t make out any tracks
Weather: Mostly sunny. -8C, no wind, but signs of drifting overnight
Snowpack:

Date of Observation: 03/16/2023
Name: Eric Murrow

Zone: Southeast Mountains
Route Description: Hwy 135 obs.

Observed avalanche activity: Yes
Avalanches: A few natural avalanches seen from the pavement. A couple small slabs in the storm snow in Green Lake Bowl on Axtel, a large avalanche in the Octagon area on Whetstone that appears to fail below the past two storms (3/10), a small avalanche on Red Mountain (could be from the warm up on Tuesday, but I suspect occurred Wednesday night/Thursday morning, and a west-facing avalanches on Round Mountain that I believe failed during warming on Thursday (looks like it failed on 3/10 interface).
Weather:
Snowpack:

Date of Observation: 03/16/2023
Name: Grant Robbins

Zone: Southeast Mountains
Route Description: Skinning up Snodgrass and across the valley appeared to be an avalanche on south aspect of Red Ridge area.

Observed avalanche activity: Yes

Date of Observation: 03/16/2023
Name: Evan Ross

Zone: Northwest Mountains
Route Description: Mt Axtell and Evans Basin. N-E-S 9,500ft to 11,600ft.

Observed avalanche activity: Yes
Avalanches: A variety of old storm slabs and loose snow avalanches that were no longer sharp looking.

East on Mt Axtell: Skier triggered 3 storm slabs. 2 small slabs were triggered on steep, unsupported pillows and didn’t have much propagation. The most notable propagated fairly wide on another steep east-facing slope at 11,300ft. The slab was about 30cm deep, and the avalanche became large in size. These slabs released on very small facets sitting on the 3/15 interface.

East in Evans Basin. Snowmobile triggered 2 small, stubborn, wind slabs that ran within the new snow, and not at the old snow interface like on Axtell.

Several small loose wet avalanches ran today in Evans Basin on E and SE slopes at NTL and ATL elevations.

Weather: Parly cloudy sky. Mostly light to calm winds. Previous transport from stronger winds in the lower Kebler corridor.

Snowpack: The Recent HST is in the range of 15 to 35cm depending on how much settlement it has seen. Similar to yesterday, east aspects produced the most notable results today, with a few soft slabs failing on the recent storm interface. They have been running on small facets above the 3/15 crust. We triggered 3 slabs on this interface. A couple ran on steep and unsupported pillows. The most notable ran on a nice plainer 40-something-degree slope. Interestingly, in the afternoon I targeted the same aspect in Evan’s Basin and was unable to get any results on the same interface on steep E and SE test slopes. The loose snow avalanches and wind slab avalanches in Evans Basin also didn’t produce results on the 3/15 interface like we had seen over on Axtell.

Steep northerly facing slopes skied nice, with a few slow-moving sluffs and one small wind slab.

Date of Observation: 03/16/2023
Name: Mark Robbins

Zone: Northwest Mountains
Route Description: Amr

Observed avalanche activity: Yes
Avalanches: Natural storm sluff in the playground, see photo

Weather: Cool air temps in the morning but the sun was doing its thing on southerlies by midday. Moderate NW winds, some evidence of wind transport in amr tenure, more evidence of cross loading over in the playground, see photo. Winds had stiffened some of the new snow on north facing terrain.