Daylight photos of lightning are hard to record. A summer daytime thunderstorm discharges a cloud to ground lightning bolt along the western edge of its rainshaft in front of the Santa Catalina Mountains, the northern border of Tucson, AZ. Other convective cellular thunderstorm are building in the distance on the left hand side as evidenced by the towering cumulonimbus clouds..Awesome and intense thunderstorms with powerful gust fronts, heavy rain, hail and lightning are common over the Arizona Desert during the summer months. Southwestern weather patterns create thunderstorms by pulling the fuel, moist air, either from the Pacific Baja side or the Gulf of Mexico and mixing it with the dry hot air rising up from the heated desert floor. Lightning is beautiful, but dangerous.