Location: Avalanche Mountain (unofficial name)

AKA:

Rock-Thunder

Elevation:

5,360+ feet

Prominence:

480 feet

State:

Washington State

Counties:

King County

In:

Middle Fork Snoqualmie Drainage, Alpine Lakes Wilderness

USGS Quad:

Snoqualmie Pass

Trip Reports
- Avalanche Mountain summit bivy
  
  2017/09/10 (2 days)
- Avalanche Mountain via Snow Lake trail
  
  2004/10/21
- Avalanche Mountain via Snow Lake trail
  
  2004/10/19
Name Origin
"'Avalanche Mountain' seemed a good name since (1) avalanches make 'snow thunder' or 'rock thunder' and (2) the Source Lake basin, just south, is famous for this treacherous phenomenon -- of both the snow and rock varieties." - John Roper in the March 1995 issue of Pack & Paddle.
The Seattle Mountaineers call this peak "Rock Thunder". This name was given by Dave Beedon, a former Seattle Mountaineers scramble leader.
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The summit of Avalanche Mountain
2017/09/11
The east side of Avalanche Mountain from point 5,360.
2012/01/07
Avalanche Mountain from NE of Chair Peak Lake
2007/08/05
Avalanche Mountain and Snoqualmie Mountain over Snow Lake
2007/08/05
Avalanche Mountain and Snoqualmie Mountain
2007/08/05
Avalanche Mountain with the upper Middle Fork Snoqualmie peaks in background
2007/05/17
Middle Fork peaks, Avalanche Mountain, and Snoqualmie Mountain over Snow Lake
2006/05/05
Avalanche Mountain, just visible from Snow Lake trail
2004/10/19

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