WASHINGTON, DC - AUGUST 22: Visitors enjoy a cool mist shower in hot weather as they visit the Smithsonian National Zoological Park August 22, 2016 in Washington, DC. Bei Bei, the youngest giant panda cub at the zoo turns one today. (Photo by Alex Wong/Getty Images)

BRISTOL, TN - AUGUST 21: Kevin Harvick, driver of the #4 Busch Beer Chevrolet, leads a pack of cars during the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Brian Lawdermilk/Getty Images)

BRISTOL, TN - AUGUST 21: Kevin Harvick, driver of the #4 Busch Beer Chevrolet, takes the checkered flag during the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Brian Lawdermilk/Getty Images)

BRISTOL, TN - AUGUST 21: Ryan Blaney, driver of the #21 Virginia Tech/Motorcraft Ford, leads a pack of cars during the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Jerry Markland/Getty Images)

BRISTOL, TN - AUGUST 21: Kevin Harvick, driver of the #4 Busch Beer Chevrolet, leads a pack of cars during the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Brian Lawdermilk/Getty Images)

BRISTOL, TN - AUGUST 21: Kevin Harvick, driver of the #4 Busch Beer Chevrolet, leads a pack of cars during the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Jerry Markland/Getty Images)

BRISTOL, TN - AUGUST 21: Kevin Harvick, driver of the #4 Busch Beer Chevrolet, leads Brad Keselowski, driver of the #2 Autotrader Ford, during the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Jerry Markland/Getty Images)

BRISTOL, TN - AUGUST 21: Kevin Harvick, driver of the #4 Busch Beer Chevrolet, leads a pack of cars during the NASCAR Sprint Cup Series Bass Pro Shops NRA Night Race at Bristol Motor Speedway on August 21, 2016 in Bristol, Tennessee. The race was delayed due to inclement weather on Saturday, August 20. (Photo by Brian Lawdermilk/Getty Images)