Sky Diary 31 May 2013 El Reno, Oklahoma, tornado - 2013-05-31 at 18-08-02

Caption: Here's a slightly zoomed-in view. Photo by Chris Kridler, SkyDiary.com, ChrisKridler.com
Aperture: ƒ/5
Shutter Speed: 1/100
Date: 5/31/13 6:08:02 PM CDT