LOUISVILLE, Ky. (WDRB) -- Temperatures in the 60s, mild weather and an afternoon and evening of air show acts and fireworks attracted an anticipated crowd of more than 500,000 people to the shores of the Ohio River in Louisville and in southern Indiana. 

The finale of fireworks raining from the Second Street (Clark Memorial Bridge) and shot from two barges on the Ohio River was accompanied by a disco music soundtrack from 9:30 p.m. to almost 10 p.m. It is often touted as the largest fireworks show in North America.

"It's really a joy to come down and run around like I used to," said Leyah Anderson of Louisville. She's attended Thunder ceremonies since childhood.

Smoke from the fireworks drifted to the southwest from the river over downtown Louisville. Those in the crowd applauded to both the visual display of pyrotechnics and the familiar, 1970s disco tunes prominent in the musical soundtrack.

Police on both sides of the river were prepared to direct the spectators to pre-planned "escape routes" once the fireworks ended. Typically, it has taken two hours or more for spectators to clear from downtown Louisville and from Clarksville and Jeffersonville, Ind.

Interstate 65 was closed from I-265 in Clark County, Ind., south to I-264, the Watterson Expressway, throughout the fireworks show and afterward. Police detoured through traffic to make it easier for departing crowds.

Prime viewing spots on the Great Lawn filled before sunset. Fireworks ended at 10 p.m., and the lawn was mostly empty, except for trash, by 10:30 p.m. However, those spectators likely faced long and slow drives home.

Elevated river levels covered part of the shorelines on both sides of the river. That was merely an inconvenience for Kathy Williams and her party, first-time Thunder goers.

"They're just happy to be here. It doesn't matter if it's grass, sand or mud. They would still be here," Williams said.

The Thunder Over Louisville air show opened with fighter jets and later a B-52 bomber flying overhead just after 3 p.m. Various air show acts were to entertain spectators through the start of the 30-minute fireworks show at 9:30 p.m. 

A large force of police, firefighters and emergency medical technicians was working to ensure safety for the spectators, primarily in downtown Louisville and at Waterfront Park in Kentucky -- and in Ashland Park and downtown Clarksville and Jeffersonville, Ind. 

The Coast Guard ordered pleasure boaters to stay off the Ohio River from McAlpine Locks and Dam upriver to Cox Park/Duffy's Landing area because of debris and swift river conditions.

Thunder and its fireworks go back to 1990; its first show on the river brought fireworks from the Second Street/Clark Memorial Bridge in 1991 and has been the opening ceremony to the Kentucky Derby Festival, at two weeks before the Kentucky Derby, ever since. 

Dozens of people gathered at the gates of Waterfront Park as early as 3 a.m. to get the best possible spot for Thunder Over Louisville.

The park's gates opened at 9 a.m., but some families gathered extra early. Chris Hieatt from Corydon, Ind., said his family was first in line and has been getting up early for the last 10 years to make sure they get the perfect spot.

Others gathered as tourists and were experiencing Thunder Over Louisville for the first time. As soon as the gates opened, bags were checked and people ran to save their section of Waterfront Park where they plan to be until the end of the fireworks show.

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