Six Flags Great America is closing at 8 p.m. today, Sunday, June 21, 2026, because of inclement weather in Gurnee, Illinois.
The earlier closing time cuts into the final stretch of the Sunday operating day at the Chicago-area amusement park. Six Flags Great America previously listed regular Sunday hours before adding the weather alert to its official park page.
Six Flags Great America Weather Close
Hurricane Harbor Chicago is part of the same Gurnee resort area. Guests heading to either gate should check the official park page before leaving, since summer weather decisions can change during the day.
Source: Six Flags Great America.