Sky Diary 20 May 2013 Duncan, Oklahoma tornado - 2013-05-20 at 17-25-20

Caption: This was an interesting feature of the storm. Photo by Chris Kridler, SkyDiary.com, ChrisKridler.com
Aperture: ƒ/4.5
Shutter Speed: 1/80
Date: 5/20/13 5:25:20 PM CDT