Thunder Mountain in the Sierra Nevada of California is located east of Silver Lake and west of Kirkwood Mountain Resort in the Eldorado National Forest. The mountain has two peaks, the 9,414ft main peak and a 9412ft sub-peak west of the main peak. The main summit is the highest point in Amador County. Due to the high elevation, most precipitation that falls on Thunder Mountain consists of snow.The peak was named by United States Forest Service personnel because "thunderstorms appear to build up in that area."