<Tr> <Th_colspan="2"> Website </Th> </Tr> <Tr> <Td_colspan="2"> thunderoverlouisville.org </Td> </Tr> <P> Thunder Over Louisville, the annual kickoff event of the Kentucky Derby Festival, is an airshow and fireworks display in Louisville, Kentucky . It is generally held each April, about two weeks before the first Saturday in May, or Derby Day . In years where Easter Sunday falls on the usually scheduled weekend, Thunder is moved a week earlier . It is the largest annual fireworks display in North America and began as part of an opening ceremonies event in 1989 with daytime fireworks. 1990 brought the first nighttime fireworks event . It officially began in its current location along the Ohio River in 1991 with fireworks, and an annual air show was added in 1992 . </P> <P> Thunder generally starts in the afternoon with an air show, followed by the fireworks show starting at 9: 30 PM, along with a synchronized soundtrack through PA and radio . An average of 625,000 people have attended each year since 1997, lining the banks of the Ohio River in Louisville, and across the river in Jeffersonville and Clarksville, Indiana . Some also watch from the river on boats, docked in positions auctioned off for charity . </P>

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