Earlier this spring, we had a spectacular storm move through. It passed slowly, with lots and lots of lightning. I got a few pictures, but only one was half-way presentable.
Storm with Lightning and Mammatus Clouds 31 March 2006, Owen County, Indiana
If you look really closely, you can see the bottom curves of mammatus clouds that formed on the back side of the storm. They’re visible as pillowy shapes descending from the mass of black across the top of the frame, backlit by the lightning strike.
The reason I’m reposting this image is that today’s Earth Science Picture of the Day is a photo of mammatus clouds, taken on the same day, of the same storm system, in Avon, Indiana. Avon is west of Indy, and north of where I live.
And, for anyone who wants to be ubergeeky, here’s a cloud identification atlas.
red paper boat 