Pro Field Report

Basic Information

Observation Details

Observation Date:
March 1, 2023
Submitted:
March 1, 2023
Observer:
SAC - Davis
Zone or Region:
Soldier and Wood River Valley Mtns
Location:
E Fork Big Wood, Croy, Baldy

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
None Experienced
I did not find a consolidated or sensitive slab in the upper reaches of the Baldy north side out-of-bounds area.

Snow Stability

Stability Rating: 
Fair
Confidence in Rating: 
Moderate
Stability Trend: 
Improving

Bottom Line

I observed two large avalanches in the E Fork of the Big Wood. I observed small slab avalanches on Della (E and N faces) and near the mouth of Deer Ck. There was very little wind affect at the top of "The Burn" on Bald Mtn. Passing clouds in the afternoon kept periods of direct sunshine fairly short.

Advanced Information

Weather Summary

Cloud Cover:
Mostly Cloudy
Temperature:
25F
Wind:
Light , SW
New/Recent Snowfall:
HST about 40-50 cm since (2/26)

Light wind shifted from SW to NW around 2 PM. It was partly to mostly cloudy. Scrappy clouds clung to mountain tops as short squalls brought moderate gusts and bouts of snow.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Photos Details
1 Mar 1, 2023
(+/- 1 day) 		E Fork Big Wood - Minebender paths
NW 8600ft 		D2 SS-Soft Slab I-New/Old Interface N-Natural
This large avalanche released above the E Fork of the Big Wood on a NW aspect at 8,600'. The avalanche ran about 1,800 vertical feet, stopping 2/3 of the way down the track. The slab initiated in wind-loaded terrain and appears to have failed on weak snow buried by snowfall since Sunday (2/26). A similar but smaller pocket released in a neighboring gully to the lookers left. This slide was obscured by new snow and likely released during intense snowfall overnight on the 28th or early on the 1st.
This large avalanche released above the E Fork of the Big Wood on a NW aspect at 8,600'. The avalanche ran about 1,800 vertical feet, stopping 2/3 of the way down the track. The slab initiated in wind-loaded terrain and appears to have failed on weak snow buried by snowfall since Sunday (2/26). A similar but smaller pocket released in a neighboring gully to the lookers left. This slide was obscured by new snow and likely released during intense snowfall overnight on the 28th or early on the 1st.
Report
E Fork Big Wood - Minebender paths

I had intermittent views into some start zones in Quigley, Croy, Indian Ck, Deer Ck, and near Morgan Ridge.

Snowpack Observations

Today was a quick glassing mission along the WRV corridor, including Croy to Rotarun, Indian Ck to Triumpf, and from the top of the Bald Mtn out of bounds (The Burn).

I found right-side-up storm snow past the rope at the top of The Burn with very little wind affect. Hand pits and pole pokes revealed storm snow over a thin 10-15 cm wind (or skier compacted?) slab atop very weak facets. The storm slab was still F throughout and lacked any strength.

Numerous tracks were dipping into the top of start zones all along The Burn from Christmas Eve to Bruce's. It was hard to tell how many skied further down the track but it appeared that at least some did.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
Wind Slab
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
 Layer Depth/Date: 50-75 cm
Comments: Shaded where expected. Some slabs exist on cross-loaded slopes at middle and lower elevations, particularly along mouths of main drainages.
Persistent Slab
Isolated
Specific
Widespread
Unreactive
Stubborn
Reactive
Touchy
D1
D1.5
D2
D2.5
D3
D3.5
D4
D4.5
D5
 Layer Depth/Date: 30-50 cm
Comments: Shaded where expected. Very little snow on middle and lower elevation sunny slopes from Baldy south. the new/old interface is obviously touchy, but any triggered slide seems like it has the distinct possibility to step down or gouge into weaker snow closer to the ground.

Terrain Use

Solo travel. I did not enter out of bounds avalanche terrain.