In a regular year the monsoon season of the desert southwest of the United States runs from early July to about September, and in a regular year it brings a fair number of thunderstorms to the desert. Once in a while some rain comes with them.
Air pushed up the sides of mountains by the surface wind and air heated by the summer sun rises and cools. Moisture pumped in from a low pressure area that forms over the Gulf Of California across southern Arizona and into New Mexico helps with the rain. Just like the sweat that forms on the outside of a glass of iced tea the moisture in the rising air condenses as it cools which forms clouds and ice and rain and nice pictures.
All of these pictures were taken with my Canon SD450 digital camera. I set the camera to take an eight second exposure at ISO 50 with the exposure compensation set to -2 and the focus set to infinity.
I took these one evening in July 2006 while standing next to my pickup with the camera resting on the roof (that's where the reflections are coming from). I held the camera at a slight angle. That's why some of the pictures are slightly blurred. I just kept snapping pictures. Sometimes I'd catch a flash of lightning during the eight second exposure and sometimes I wouldn't. A lot of the flashes were the kind where the flash would repeat two or three times in the same location. That was usually way too much light and they would end up way over exposed. The bolt had to be just one single flash to have a chance of looking good.
If I'd have known they were going to be this good I would have done a better job. This was just a spur of the moment experiment. Next storm.