Professional Field Report

Basic Information

Observation Details

Observation Date:
January 1, 2020
Submitted:
January 2, 2020
Observer:
SAC - Savage
Zone or Region:
Galena Summit and Eastern Mtns
Location:
Titus Ridge to 9400', eastern side of the ridge

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
Isolated
Collapsing? 
None Experienced
Observed avalanche in Eagle Ck headwaters and small avalanche on road cut below Titus Lake summer trailhead while driving up to Galena Summit at 1600hrs. Cracking was in somewhat exposed, steep SE facing rocky area around 9300' (very soft slab of just new snow cracking on top of 12/31 surface).

Snow Stability

Stability Rating: 
Poor
Confidence in Rating: 
High
Stability Trend: 

Bottom Line

Lots of evidence of instability on SE aspects: significant natural slide in headwaters of Eagle Creek, small pockets that slid observed on the drive up to Galena Summit, a soft, shallow (6-12" thick) but wide (400 ft) natural or remote triggered slide at the top of the pass, cracking in very soft slabs at ridgeline, and poor stability test scores on our old buried surface hoar layer. Add the strong winds with lots of wind loading in other places - especially upper elevations - and you have a bad setup.

Advanced Information

Weather Summary

Cloud Cover:
Obscured
Temperature:
20F
Wind:
Moderate , NW

12-20cm (5-8") of new storm snow by dark. Snowing S-1 to S3 while I was out for 90 minutes (4 PM until dark). There was snow on tree limbs from the pass to the top of the first bump at about 9600', but I could hear the wind cranking at higher elevations. There was a lot of snow available for transport.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Comments Photo
1 Eagle Creek headwaters
SE alpine 		D2 U N-Natural Terrible vis for viewing avalanche activity when I was driving up to the pass around 3 PM, but there was a donut hole around Eagle Creek. I saw one obvious debris pile in the headwaters area, at least a D2. None
1 Galena Summit ("Verlons")
SE 8900 		D1.5 SS I-New/Old Interface 25cm (10") U-Unknown Slide occurred between 4-4:30PM while I was on Titus Ridge. It was either remotely ski triggered from hundreds of feet above on the flat ridge or a natural. The plow did not trigger it (conversation with plow driver). Instagram video link https://www.instagram.com/p/B60onF2gAH4/

Touchy new snow interface on middle elevation SE aspects. I also saw a small road cut a half mile before the top of the pass that had released naturally, also less than a foot thick.

Snowpack Observations

9100' SE aspect: 80cm depth. 18cm new snow, 12/11 crust+FC at 44cm, 12/7 SH at 15cm. ECTN18 on 12/7 SH at 15cm. PST22/100end, SP, on 12/7 at 15cm. CPST25/100end, SP, on 12/7 at 15 cm.

Jan 1, 2020 snowpit on SE aspect near 9100' on Titus Ridge.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
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: 12/31 interface of FC+crust 20cm down, also 12/7 SH down 65cm (2 feet)
Comments: The 12/31 interface is quite touchy but slides will be small. The 12/7 layer is still showing poor test scores but has been very stubborn leading up to this storm.

Only observed a limited wedge of middle elevation terrain in short 1hr walk.

Terrain Use

All avalanche terrain was off-limits. Quick solo tour out the ridge just before dark.