After a hot and humid day, thunderstorms could hit parts of the Chicago area Wednesday night.
The storms are expected to develop across the area from the late afternoon into the evening hours.
Some of the thunderstorms could become strong to severe, particularly during the evening hours, bringing the potential for hail, damaging winds and heavy downpours.
The heaviest rainfall is expected to hit areas south of Chicago from Dixon to Joliet and into Rensselaer, Indiana.
The storms will continue overnight into early Thursday morning.
The National Weather Service warns that flooding will continue on many area rivers and new rises are possible if heavy rain occurs.
This follows weeks of flooding in numerous northern Illinois communities, which have had little relief from the rain and storms so far this month.