The Ausable Bayfield Conservation Authority says with the possibility of 15-30 mm of rain over the next 36 hours, watercourses could approach or exceed their banks.
Based on the current forecast, water levels would peak Thursday, and remain elevated into the weekend.
Streamflow estimates suggest major flooding is unlikely, but a combination of heavy rain on saturated or frozen ground, could result in a quick rise in water levels in streams and rivers.
Residents are reminded to avoid all watercourses due the extremely cold water temperatures, and slippery unstable banks.
Ice covered water should be considered unsafe.