The Essex Region Conservation Authority has issued a flood watch with a rain warning in effect from Environment Canada.
The authority stated that with the significant rain that already fell early Wednesday afternoon and the amount of rain still in the forecast flooding may occur.
The Essex region already received around 25-35 mm of rain Wednesday.
Environment Canada said some areas could get as much as 50mm of rain.
Heavy downpours can cause flash floods and water pooling on roads. Localized flooding in low-lying areas is possible.
The flood watch will stay in effect until noon Thursday.