| Good afternoon, Chicago. Toward the middle of the day Sunday, as tens of thousands of runners race in the Bank of America Chicago Marathon, temperatures are forecast to climb into the low 70s to 80 degrees. It’s not the worst kind of weather for a long run. But it is unseasonably warm — the normal high for Oct. 11 is 65 degrees — and “it’s less than ideal,” said George Chiampas, chief medical and safety officer for the marathon since 2007 and an emergency physician at Northwestern Memorial Hospital. “Everybody should respect the weather,” he told the Tribune. So organizers are asking participants to heed their warning system’s yellow flag for Sunday by adjusting their pace, slowing down and staying hydrated. Here’s what else is happening today. And remember, for the latest breaking news in Chicago, visit chicagotribune.com/latest-headlines and sign up to get our alerts on all your devices. Subscribe to more newsletters | Asking Eric | Horoscopes | Puzzles & Games | Today in History news Children stare at the Booster K1 robot at the annual University of Chicago South Side Science Festival in Hyde Park on Oct. 3, 2026. (Arthur Maiorella/Chicago Tribune) Robots demonstrating dance moves made popular by the late entertainer Michael Jackson, mini-catapults sending plastic gourds soaring toward a cauldron, paper airplane competitions and ice cream frozen by liquid nitrogen were among the demonstrations on offer at the fifth annual University of Chicago South Side Science Festival. More top news stories: business Workers prepare the main stage ahead of the Obama Presidential Center dedication ceremony on June 18, 2026. (Brian Cassella/Chicago Tribune) Months after former President Barack Obama’s museum’s opening this summer, employees at the museum foundation announced today they are organizing a union. More top business stories: sports White Sox pitcher Mike Vasil runs to the field during a workout at Rate Field on Oct. 6, 2026, in Chicago. (Armando L. Sanchez/Chicago Tribune) It’s a beautiful day for a Blackout Game, though a little bit on the toasty side for Chicago White Sox fans heading out to the Rate for Game 3 of the American League Division Series. More top sports stories: eat. watch. do. Mario Abney, co-founder and CEO, right, dances as Kevin Nabors and other members of the Windy City Ramblers perform at the 95th/Dan Ryan Red Line CTA station in Roseland on Oct. 1, 2026, at the culmination of the Red Line Jazz Festival. (Eileen T. Meslar/Chicago Tribune) Summer is over, but music festival season very much isn’t. At least not for classical, jazz and experimental fans. More top Eat. Watch. Do. stories: nation & world This satellite image from the National Oceanic and Atmospheric Administration shows Tropical Depression Nine forming over the Gulf of Mexico on Oct. 6, 2026. (NOAA via AP) Tropical Storm Isaias formed early today in the warm waters off eastern Mexico and forecasters said it was expected to strengthen into the first hurricane of the Atlantic season before hitting the U.S. Gulf Coast later in the week. More top stories from around the world: | 
