Northwest Avalanche Center

Observation: Public

All Observations

Observation Details

Name:
Daniel MacDonald
Observation Date:
May 4, 2022
Submitted:
May 5, 2022
Zone or Region:
Mt Hood
Activity:
Skiing/Snowboarding
Location:
Coalman & Upper Zigzag Glaciers

Observed Avalanches

Did you observe any avalanches? 
Yes
Avalanche Type:
Other
Size:
Size 2: Could bury, injure, or kill a person
Elevation:
11000-9500
Aspect:
SW
Comments:
2 separate D1-1.5 slab avys max 50-100’ across w crowns measured in inches, both likely initiated via large Rime/Rock fall. One ran from 11K’ to 10.2K’ over Hot Rocks and appeared to include at least one step down (also measured in inches) early on. The other initiated from base of Crater Rock and ran from 10.2K’-9.5K’, consistently wider and with larger debris.

Signs of Unstable Snow

None reported

Observations

Pictures will hopefully upload in order to highlight this description:

First noticed the higher avalanche while climbing up to Hogsback enroute to climber’s right hand Pearly Gate [side note: Until the late afternoon summit when SW winds began to pick up, very enjoyable climbing conditions throughout the day, minimal wind and warming despite NOAA forecast and well-tracked route well-suited to basic mountaineering gear…guessing coming storm system will preserve or enhance that for awhile longer…while initially worsening storm and wind avalanche risks]. After ski descending Mazamas Chute (also in great shape), inspected this Rimefall-initiated slide more closely and noticed the multiple levels seeming to indicate a stepdown. Also realized that rather than terminating just above Hot Rocks, it slide through it and deposited toe debris just below.

Noticed the lower avalanche after entering onto Upper Zigzag just below Crater Rock, from whose notch it appeared to initiate, also implying some form of Rime or maybe Rock fall. No step down noticed on this one, though was wider and with larger debris than the first.

Also including some pics at the end related to wind-loading evidence (as appears to me). With ongoing STRONG WSW winds forecasted to continue during the duration of this weekend’s cold-tailend storm, I would think these high elevation, wind-based slab avalanche risks will continue (or worsen) in the days ahead for the same affected (primarily Eastern half) aspects.

Media

Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Public Field Report: Coalman & Upper Zigzag Glaciers
Less dense snow on climbers left of Hogsback
Denser slab like snow on climbers right of Hogsback
Great connecting traverse trail, except with certain ski carrying setups
First time up right side. 6’ of recent snow apparently does wonders for technical ice steppes
Is it me, or did this thing grow significantly in the last 10 days?
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