Mammatus Matrix

Subtle mammatus ride the clouds of an approaching storm in this view of the northeast sky as seen from North Marion Road, about .1-mile north of County Home Road and 2.5 miles north of Marion, Iowa. Top photo was imaged at 7:32 PM, Thursday, July 25, 2013 and the bottom, one minute later. The bottom image includes Yellow Coneflower, and Iowa prairie wild flower, in the foreground. The storm was about 1 1/2 hours from the Cedar Rapids area, eventually dropping 1.76 inches of rain at my home location.