Observation: NWAC Forecaster

All Observations

Basic Information

Observation Details

Observation Date:
December 28, 2021
Submitted:
December 28, 2021
Observer:
NWAC Forecaster - Dallas Glass
Zone or Region:
Snoqualmie Pass
Location:
Chair Peak/ Snow Lake (All aspects near treeline. E-S-W below treeline)

Signs of Unstable Snow

Recent Avalanches? 
Yes
Cracking? 
None Experienced
Collapsing? 
None Experienced

Media/Attachments

Small loose dry avalanches like these have been common this week.
A very large avalanche from Dec26 omn Chair Peak. SS-N-R2-D2.5-U, NE-E, 5800'
The southern end of the crown from the Chair Peak avalanche. Dec 26, NE-E 5800'

Advanced Information

Weather Summary

Cloud Cover:
Overcast
Temperature:
11°F
Wind:
Calm
New/Recent Snowfall:
Strom total: 4-5 ft (120-150cm). 24hr snow total: 2-3 inches (5-8cm)

Mostly overcast skies with occasional sun breaks. Cold. Very light snow showers for much of the morning.

Avalanche Observations

 #  Date Location Size Type Bed Sfc Depth Trigger Photos Details
1 Dec 27, 2021
() 		Cache Couloir
NE 4800ft 		D1.5
R2 		SS-Soft Slab I-New/Old Interface 1.5ft U-Unknown Report
1 Dec 26, 2021
() 		Upper Basin of Chair Peak
E 5800ft 		D2.5
R2 		SS-Soft Slab 3ft N-Natural
The southern end of the crown from the Chair Peak avalanche. Dec 26, NE-E 5800'
A very large avalanche from Dec26 omn Chair Peak. SS-N-R2-D2.5-U, NE-E, 5800'
Report
Cache Couloir
Upper Basin of Chair Peak

Plenty of small loose dry and soft storm slab avalanches from the past several days were visible on most very steep and rocky slopes.

Snowpack Observations

The snow surface consists of large (2+mm) stellar. The upper snowpack is right side up. Generally 3-4' (90-120cm) over the Solstice Crust. A very thin and breakable sun crust formed on steep southerly aspects on 12/27. Other than this crust the upper snowpack is generally settling without any layers of concern.

HS: @3800': 285cm @4300': 300-320cm

Old wind affected snow was visible, but covered with new snow. No new wind transported snow was observed.

Avalanche Problems

Problem Location Distribution Sensitivity Size Comments
None Specified
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