The National Weather Service says showers and thunderstorms over the last week - combined with expected wet weather - have put the region at risk for flash flooding.
Meteorologists say storms have already dumped several inches of rain over parts of southeast Missouri, southern Illinois, western Kentucky and southwest Indiana.
While severe weather is not expected, experts say high water could cause travel trouble - and in come cases, could happen quickly, creating dangerous conditions.
June was already the wettest month on record for the state of Illinois. Forecasts call for a clearing sky by Friday evening and into the weekend, with warmer temperatures as well.