Upward Discharge

This upward cloud-to-cloud lightning discharge took place in an approaching thunderstorm in Cedar Rapids, Iowa at 10:15 PM on July 23, 2010. The 1,000-foot transmitter tower visible in the distance at lower left is operated by KCRG-TV9 and is located in northwest Hiawatha. CTC lightning is the most common type of lightning. In this scenario, lightning travels from the negatively charged base of one cloud to the positively charged top of another. Lightning can travel at speeds of up to 130,000 mph.