The Lower Thames Valley Conservation Authority (LTVCA) is monitoring a system that could bring up to 80 millimeters of rain.
A flood outlook has been issued for the potential of showers and thunderstorms developing over the region late Monday night and continuing through Tuesday.
"Forecasts suggest that the region could see between 30 and 80 millimetres of rain over the next two days," read the notice from LTVCA. "Further rain predicted for later in the week could push these rainfall totals even higher. Given the recent rain last week and the lack of ground cover at this time of the year, much of this rain would be expected to run off into the region’s watercourses."
Watercourses are expected to rise based on the forecast, which may lead to flooding in low-lying areas.
The LTVCA said the McGregor Creek Diversion Channel in Chatham may be activated depending on the actual rainfall.
The situation will be watched, and any updates will be passed along.