This week’s snowpack summary is here. The week brought a potent wind event with modest storm totals, a prominent dust layer, and more large cornice falls.
Wet slide anthracites
Date of Observation: 04/06/2023
Name: Emma Vosburg
Zone: Northwest Mountains
Route Description: Anthracites playground
Observed avalanche activity: Yes
Avalanches: South facing wet slide in the playground behind the anthracites. Human triggered slide on the dust/crust layer.
Started small and picked up speed to the bottom of the slope ~ 300ft down
Weather: 4/6. 2:30pm. 30 degrees no wind blue skies
More cornice falls and wet loosies
Date of Observation: 04/07/2023
Name: Zach Guy
Zone: Northwest Mountains
Route Description: Scarp Ridge to Peeler Peak and out OBJ basin, traveling on various aspects to 12,200′
Observed avalanche activity: Yes
Avalanches: Several more large cornice falls that ran sometime in the past couple of days. An uptick in small wet loose activity today, generally on the southern half of the compass at higher elevations and the most action below treeline on east to northeast aspects. We skier triggered a couple of small wet loose slides on northeast aspects below treeline.
Weather: Warm, clear all morning with cloud cover increasing this afternoon.
Snowpack: About 6″ of settled storm snow over the dusty storm interface. The snow became wet on all but NE to NW aspects N/ATL and due north BTL. A pit on a SE aspect NTL in Peeler Basin produced propagating results about 2 feet deep down on the 3/30 interface, a faceted crust. There are several crusts in the upper 3 feet of the snowpack that could pose a concern for wet slab issues if we see a rapid influx of meltwater next week. Currently only the recent storm snow is wet and the 4/3 crust remained frozen except for low elevation southerlies.
- Cornice fall Owen/Purple saddle
- Cornice Fall Scarp Ridge
- Cornice Fall Richmond
- Cornice Falls near Richmond, documented in Sam’s ob. One of these triggered a slab.
- Propagating test results on a SE aspect NTL
- Wet Loose Rustler’s Gulch
- Wet loose on east aspects of Peeler
- Skier triggered wet loose on a NE aspect BTL of Peeler
- Wet loose on Beckwith
Cornice fall and roller balls
Date of Observation: 04/07/2023
Name: Sam Lesnikoski
Zone: Northwest Mountains
Route Description: Up over daisy pass, ascended the saddle between Richmond and Hancock to Hancock summit, back over daisy to baxter
Observed avalanche activity: Yes
Avalanches: Cornice fall and associated shallow slab on Hancock/Richmond saddle, ran yesterday? Small skier triggered wet sluffs on lower, more easterly facing Hancock benches. Innumerable natural wet slides and sluffs running on dust, all fairly small.
Weather: Sunny and hot with increasing cloud cover by afternoon
Snowpack: Dry and pleasant snow on high northerlies, anything with a bit of east in it was wet by around 11.
More naturals from the last storm in the Ruby Range
Date of Observation: 04/06/2023
Name: Zach Guy
Zone: Northwest Mountains
Route Description: Viewed from Mineral Point
Observed avalanche activity: Yes
Avalanches: Several D1 to D2 wind slabs ran during the storm, some related to cornice fall. See photos and details below.
- Cornice + wind slab combo. Angel Pass.
- Wind slab on the Shield.
- Fresh cornice fall on left, slab on the right. Garfield Peak.
- Wind slabs on Mt. Gunnison (outside of our forecast area)
- Cornice + wind slab combo near the Nipple
- East face of the Ant. Not sure if this ran 3/31 storm or 4/4 storm.
Fresh cornice falls, sluffing, and some recent wind slabs in the Ruby Range
Date of Observation: 04/06/2023
Name: Zach Guy
Zone: Northwest Mountains
Route Description: Traveled on various aspects on Mineral Point and Cascade to 12,500′.
Observed avalanche activity: Yes
Avalanches: Numerous small dry loose avalanches ran today on northerly terrain, and we ski-triggered more of the same (D1). A couple small wet loose ran on an E/SE aspect BTL of Cascade (D1). Several large cornice falls failed sometime since the storm ended, past 48 hours (D2). Several D1 to D2 wind slabs ran during the storm, some related to cornice fall. See photos and details below, the storm-related avalanches are coded in a separate ob.
Weather: Clear skies, calm winds, cold temps near zero this morning rising to 20F at 12k midday.
Snowpack: There’s about a foot of fairly dense storm snow near and above treeline in the Ruby Range with signs of previous drifting. The snow appears to be bonding well to the storm interface, based on targeted feedback from numerous steep test features. We got some shallow cracking a few inches deep from the most recent drifting. The snow stayed dry on northerlies, got a little moist on easterlies, and just the surface got wet on southerlies. The dust is resurfacing on low-elevation southerlies near town.
- Fresh cornice fall on Garfield and a wind slab that likely ran during the last storm.
- Fresh cornice fall and an older slab on East Beckwith
- Fresh cornice fall above Middle Anthracite Creek.
- Small wet loose avalanche ran today on Cascade.
- Skier triggered loose dry avalanches on north side of Cascade.
Mostly strong and quite supportive snowpack in the shallower parts of the Elks
Date of Observation: 04/05/2023
Name: Ben Pritchett
Zone: Southeast Mountains
Route Description: Cement Creek to Hunter Creek to Star Pass
Observed avalanche activity: Yes
Avalanches: One small cornice-triggered D1 slab in the Timbered Hill Chutes, which looked like it ran Sunday at the end of the last warm-up. The cornice chunks and debris gouged like the snow was wet a the time.
Weather: Broken skies, flat light, cold temperatures, and nearly calm westerly winds.
Snowpack: Below treeline, the snowpack on all aspects has undergone 4 melt-freeze cycles in the last month (2x in early March, the beginning of the March 20 storm, and late March warm-up). These crusts had water percolate between them repeatedly, making for a very stout upper snowpack structure now. Even at the upper elevations of this elevation band on shady slopes where thin crusts formed, we found no weak layers of concern.
Mostly quiet on Axtell
Date of Observation: 04/05/2023
Name: Zach Guy
Zone: Northwest Mountains
Route Description: Mt. Axtell, traveled mostly on N to E aspects to 11,900′.
Observed avalanche activity: Yes
Avalanches: Skier triggered and observed a few natural loose avalanches, small in size (D1). Ski cut a small wind slab about 6′ wide, 12″ deep on a crossdrifted north facing slope NTL (D1). There was a thin natural windslab below ridgeline in 4th Bowl, about 4″ deep.
Weather: Partly to mostly cloudy with a few afternoon flurries (S-1). Light winds, no transport.
Snowpack: About 4″ to 5″ of storm snow, delineated by a prominent dust layer near the bottom of the storm. I found a few drifts up to a foot thick in typical locations; ski cuts and stomps were unproductive except one small pocket. It seems most of the wind transport here happened early in the storm before there was much snow available for transport. The last few inches of snow were relatively unaffected by wind and also concealed some of the previous drifting textures.
- Shallow sluffing on a very steep, BTL slope where the snow surface was starting to get moist.
- Stomped around above a few slopes where I thought I might get some wind slab feedback but they were quiet.
- Skier triggered a small wind slab on a steep, unsupported feature.
- A small natural loose avalanche in the Pencil.
- A very thin wind slab on 4th Bowl
From Dust to Dust (Go Back to the Desert)…
Date of Observation: 04/05/2023
Name: Travis Colbert
Zone: Southeast Mountains
Route Description: Washington Gulch TH; W & E sides of Snodgrass; 9,400-11,000 ft mostly SW & NE aspects.
Observed avalanche activity: No
Snowpack: Fresh dust on a red, dusty crust; with the first dust mentioned quickly turning to mush. Tomorrow I must venture to Saleeda to tread lightly on red, dusty dust.
This riddle, or is it a poem, was inspired by all the bad (good) riddles of Ted Lasso (I have been binge watching) and to a lesser degree by yesterday’s historic indictment of our illustrious/notorious (depending on your persuasion) Donald J Trump :)
OK, for real, sunny aspects were supportive to skis (dust on crust as described above), while the more northerly aspects were dry & soft.
Photos:Dust
Date of Observation: 04/04/2023
Name: Eric Murrow
Zone: Northwest Mountains
Route Description: Kebler Pass to Scarp Ridge on snowmobile and ski tour around the Anthracites.
Observed avalanche activity: Yes
Avalanches: Visibility was poor much of the day, but I could see storm snow debris on a drifted easterly slope near treeline at the top of the Playground in the Anthracites. This feature has a large fetch for gathering snow.
Weather: Mostly cloudy skies with consistent light snow with a few short periods of S2. Storm total of 6 inches around 4pm at 11,000 feet. Moderate wind speeds on near treeline ridgeline. It is hard to miss the dust at the base of the storm snow, yuck.
Snowpack: Crusts at the old snow surface, just over 11,000 feet, were 3-4cm on southeast slopes, 2cm on east terrain, and thinned away as you move into northeast aspects. North-facing slopes in this area remain fully dry and provided nice turns. I was able to produce a few shooting cracks on drifted near treeline features, but fetches were relatively small so wind slab formation was only a few inches thick.
- Shallow shooting cracks on a drifted northerly feature in the Anthracites.
- About 6 inches of storm snow resting on a dusty crust on a NE facing slope.
- A supportive to skis crust on a southeast-facing slope at 11,300 feet.
- A 2 cm crust on an east slope just over 11,000 feet.