
Chicago endured one of its torrential rainfall events from September 2023 on, leading to flooded basements.
Before 9 p.m., a single thunderstorm cell formed over Chicago as a result of the outflow boundary moving northward into the city from earlier storms south of Interstate 80.
This system stalled, developing "training" thunderstorms, where intense rainfall repeatedly hits the same area until about 10:45 p.m.
The Garfield Park area recorded a surprising 4.63 inches of rain in just 90 minutes, with a storm total of 5.45 inches.
The Loop got 3.81 inches in just under two hours, while radar projects over the Eisenhower Expressway corridor west of downtown displayed totals nearing 7 inches.
The meteorological department issued a flash flood warning at 9:46 p.m. and eventually upgraded it to a “considerable” level by 10:06 p.m., triggering emergency notifications.
This warning level is often linked with a catastrophic flooding event.
Experts attribute the torrential downpours to climate change. With every 1°F rise in temperature, the atmosphere holds up to 4% more moisture, leading to intense rainfall.
According to Climate Central, rainfall intensity in Chicago has increased by 8% since 1970, posing a threat to the city’s infrastructure.