From the National Weather Service in St. Louis—–
A Flash Flood Watch has been issued for east central Missouri, the STL Metropolitan area, and west central Illinois, from 7:00PM this evening until tomorrow morning. Heavy downpours from strong thunderstorms will induce flash flooding in flood-prone areas. Do not drive through water of any depth, make sure that cell phone and flashlight batteries are charged in case flood waters approach, and keep informed of the latest forecast for updates.