This is a radar image from the approximate time the photograph was taken.  The photographer was located in Wapakoneta, Ohio, facing south.  Note the weak line on radar extending from northern Montgomery County, across Miami County and into southern Shelby County.  This is the gust front, or leading edge of rain-cooled air produced by the thunderstorms across western Ohio.  Gust fronts are usually shallow, and become harder to detect on radar as they get farther away.  Thus, the gust front "disappears" in Shelby County on this image.  However, it actually extends as far north as Auglaize County, where the photographer was able to capture it and its associated shelf cloud with his camera.