NWS / NOAA weather: Flash Flood Warning issued July 4 at 3:37PM CDT until July 4 at 7:00PM CDT by NWS Chicago IL

At 337 PM CDT, Doppler radar and automated rain gauges indicated
intense thunderstorms with rainfall rates up to 3 inches per hour
continuing across the area. Due to very slow moving thunderstorms,
up to 3 inches of rainfall has occurred in about 1 hour near Big
Rock and Kaneville. Significant flash flood impacts are imminent.

HAZARD...Significant flash flooding.

SOURCE...Radar and automated gauges.

IMPACT...Rapid-onset, significant flooding of creeks, streams,
drainage ditches, low-lying areas, and poor drainage
areas. Widespread street and underpass flooding.
Possible flooding of structures. Possible flooding of
highways.

Some locations that will experience flash flooding include...
Aurora, St. Charles, West Chicago, Batavia, Geneva, Montgomery,
North Aurora, Sugar Grove, Elburn, Big Rock and Kaneville.

Source: NWS / NOAA weather.