I was filming a lightning storm from my patio on July 21, 2008, and captured a couple of interesting sounds, that occurred almost simultaneously with the lightning. I posted a short blog about it at the time, but got more interested, and now Kevin Knupp of UAH and John tarvin of Samford University have submitted a note to Monthly Weather Review on this, with spectrograms of the sound and frame-by-frame analysis of the video (1/30 of a second), showing light and sound intensity vs. time. These sounds are not thunder. A video with both instances of the sounds is now on youtube, with the clips played at regular time and slowed down.
