Date of Observation: 04/10/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: West and Middle Brush Creeks.

Observed avalanche activity: Yes
Avalanches: Documenting yesterday’s avalanches from West Brush. See other ob for today’s wet avy’s.

Date of Observation: 04/10/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: West Brush Creek drainage and Teocalli Mtn to 13,200. Traveled on various aspects, back to the TH by 2 before the peak of meltwater drainage.

Observed avalanche activity: Yes
Avalanches: See photos and details below. Yesterday’s slides are documented in separate ob.
BTL: Several large gouging wet loose, wet slabs and glide avalanches ran yesterday. Activity was escalating today, we observed three wet slabs run between 1 p.m and 2 p.m on east aspects (D2-D2.5) and a full-depth wet loose on a south aspect (D2). The wet slabs failed just above the ground and one snapped fairly mature trees.
NTL: A few shallow wet loose (D1-1.5) ran yesterday, along with several large wet slabs (D2) on south to west aspects, in shallow, rocky terrain. Saw one wet slab run today on an east aspect (D1.5) and some more small wet loose activity. Left before the south to west aspects were at peak instability.
ATL: A few fresh cornice falls (D2) and a few shallow wet loose avalanches (D1-1.5). Notably quieter than mid and low elevations for wet activity.
Also a notable D3+ came off of the south face of Teo about a week ago (I’m guessing April 1). It started as a broad storm slab ATL and stepped down into old hard slabs in the gullies before reaching valley bottom.
Weather: Clear, calm winds, sweating profusely by mid day.
Snowpack: Surfaces were frozen and supportive to boot, ski, and sled this morning for a few hours. By about 12:30, east aspects BTL were unsupportive in steep, rocky areas (boot pen thigh+ deep), and small test slopes were easy to initiate gouging wet loose. Wet slab activity began shortly after that here. High northerly aspects remained dry, but were just starting to get damp and rollerball on NE aspects around 12,000′. On planar sunbaked slopes ATL (not near rocks), water had moved into the top 5″ or so. Sledding out became on and off trapdoor this afternoon. The dust is now widespread on the surface at all elevations in the SE mtns, except for high north.

Date of Observation: 04/09/2023
Name: Zach Guy

Zone: Southeast Mountains
Route Description: Obs from town.

Observed avalanche activity: Yes
Avalanches: Several large natural avalanches running out of the westerly side (Terminator Chutes) of Mount Crested Butte. These ran around 6 or 7pm.
Weather:
Snowpack:

Date of Observation: 04/09/2023
Name: Eric Murrow

Zone: Northwest Mountains
Route Description: Kebler Pass corridor to Evan Basin on Emmons and up to Scarp Ridge.

Observed avalanche activity: Yes
Avalanches: A recent glide avalanche on an easterly aspect of Whetstone BTL on shale slopes, a handful of small wet loose avalanches near treeline, and fresh cornice fall on Emmons along skin track ridge near treeline.
Weather: Some cloud cover in the morning gave way to mostly clear skies by noon and the afternoon. Warm temperatures below treeline, near freezing temps above treeline, and light west-northwest winds at ridgetops.
Snowpack: I traveled around in the afternoon to catch peak warming on easterly and southerly slopes. Below treeline surface crusts lost strength just after noon and I found up to a foot of wet cohesionless snow below. The snowpack strength ramps up not much below the wet snow which leaves a foot or more of wet snow on low elevation sunny slopes for loose snow avalanches to entrainment. Near treeline on an easterly slope , wet snow was limited to the top few inches making for easy, small loose avalanches. Meltwater had drained down to and was oozing through the first crust encounter beneath the dusty crust near the surface. An above treeline a southeast slope was only moist/barely wet in the top few inches. I was able to produce roller balls here, but do not think it was a Wet Loose avalanche problem yet; light winds and modest temps kept alpine sunny slopes in this area from becoming a problem.
There was a dramatic difference between water production on terrain with dirt at or very near the surface versus slopes with 6 inches or more of white snow.

Date of Observation: 04/09/2023
Name: Zach Guy

Zone: Northwest Mountains
Route Description: Rec tour this morning on Purple Peak, traveling on southerly an northeast aspects up to 12,800′

Observed avalanche activity: Yes
Avalanches: Two new alpine cornice falls since I was last in this area on the afternoon of 4/7 (D1.5 and D3) and a recent glide avalanche off of rocks on West Beckwith (D1.5)
Weather: Mid-level clouds passed overhead a few times but still lots of solar input. Light winds.
Snowpack: High northerly aspects held dry, stable powder. Surfaces were well-frozen this morning at all elevations. By 11:30 a.m., rollerballs and pinwheels started coming off of rock bands on east aspects NTL as the top few inches got wet. Good corn skiing at that time on southeast NTL. Above treeline south has only seen meltwater go a few inches deep during the last few days. On below treeline south, there were timber sled tracks sinking in about 10″.

Date of Observation: 04/08/2023
Name: Eric Murrow

Zone: Northwest Mountains
Route Description: Washington Gulch to Mount Baldy’s sunny side.

Observed avalanche activity: No
Avalanches: Decent views into the Ruby Range did not reveal any new cornice falls.
Weather: Increasing cloudiness late morning turned to sporadic snow showers midday. Mild temperatures and moderate SW wind in the afternoon at ridgetop.
Snowpack: Cloudiness limited the Wet Loose avalanche concerns in the area I traveled. Surface crusts softened but didn’t break down during the day. I dug a couple of test profiles looking at east and southeast features – the snowpack generally looks strong in the upper snowpack given the number of crusts and ice columns from recent warm weather. Faceting above a late March crust, on two different slopes (E and SE), appears to be a potential failure plane if flooded by meltwater. Northeasterly slopes below treeline have several soft crusts, with dry snow between, in the upper 18 inches of the snowpack that could be available for entrainment once the water production resumes in the coming days.

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

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.

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.