From August 11 to August 15, 2025, multiple rounds of thunderstorms affected parts of the Midwest, including northern Illinois, northwest Indiana, southern Wisconsin, east central Minnesota, and Colorado. Initially, scattered showers and isolated thunderstorms brought lightning, brief heavy downpours, and gusty winds, with some storms producing pea-sized hail and gusts up to 60 mph, particularly south of a Mendota to Waukegan line in Illinois. These storms caused concerns for localized flooding due to torrential rainfall. On August 15, similar weather conditions were reported in Colorado, with wind gusts expected between 40 to 50 mph and temperatures warmer than average for mid-August. The National Weather Service offices in Chicago, Boulder, Milwaukee, and the Twin Cities highlighted the potential for damaging winds, heavy downpours, and localized flooding across the affected regions through the weekend.