IndyCar driver Nolan Siegel was not cleared to race at Iowa Speedway because of a mild concussion suffered in a crash Saturday.

It was the right-front tire that failed on Kyle Kirkwood’s Andretti Global Honda on Saturday at Iowa Speedway, and while his No. 27 Honda made it to the finish line unscathed on Sunday, Kirkwood’s teammates weren’t as fortunate as similar right-front tire failures led to crashes for Marcus Ericsson

Arrow McLaren driver Nolan Siegel missed race two at Iowa Speedway after not getting medically cleared to compete.

After an afternoon filled with tornado sirens, lightning strikes, torrential rain and visible cloud rotation near Iowa Speedway, IndyCar canceled Friday afternoon practice.

Chad Hahn, warning coordination meteorologist at the National Weather Service, also confirmed a tornado did not touch down in Newton or Jasper County. He said there was a strong rotating wall cloud on the storm, which along with the rotation identified on radar prompted the tornado warning.

"It saved me a headache." IndyCar's aeroscreen was tested for the first time in race at Iowa Speedway five years ago.

Sunday at Iowa Speedway must have felt like June’s World Wide Technologies Raceway race all over again for Team Penske. Its Chevy-powered trio of Josef Newgarden, Will Power and Scott McLaughlin had the speed to fill the WWTR podium,