Sunday’s NASCAR in Chicago update can be found here.

CHICAGO — NASCAR has announced that Saturday’s Xfinity Series’ Loop 121 street race has been postponed due to weather and lightning in the downtown Chicago area.

The race will resume at 10 a.m., with gates opening to the general public at 9 a.m.

“Due to the potential for continued lightning strikes and in the interest of public safety and caution, the facility needed to be evacuated,” a NASCAR spokesperson told WGN News. “NASCAR had hoped to resume activities, but not until city officials allowed fans to return to the grandstands. The forecast for lightning extends into the next several hours, forcing NASCAR to postpone the completion of the NASCAR Xfinity Series race until (Sunday) morning.”

The decision was made just after 6:30 p.m. to suspend the Loop 121 street race until Sunday. The Xfinity Series race in Chicago is scheduled for 55 laps and 121 miles.

The Chainsmokers concert, scheduled for 7 p.m., has also been canceled and will not be rescheduled.

Cole Custer led each of the first 25 laps Saturday before the delay because of a lightning strike in the area. John Hunter Nemechek was second, followed by Justin Allgaier, Brett Moffitt and Austin Hill.

Severe weather was a cause of concern as Chicago was set to hold the inaugural Chicago Street Race weekend. WGN meteorologist Mike Janssen said there was a 50% chance of storms for Saturday when the Xfinity Race was scheduled to start at 4 p.m.

While some NASCAR races have continued in the rain, lightning in the area proved too great a hurdle for drivers.

Sunday morning may be no different.

Janssen’s latest computer forecast model calls for heavy rain, jeopardizing the Loop 121 street race and the NASCAR Cup Series. As a result, the green flag for Sunday’s NASCAR Cup Series Grant Park 220 has been moved up to 4:05 p.m.

NASCAR announced that single-day tickets are still available for Sunday.

The Associated Press contributed to this report.