Environment Canada has issued a Special Weather Statement for Windsor-Essex due to heavy rain in the forecast.
The National Weather Service is calling for significant rainfall on Wednesday, with rain heavy at times beginning Wednesday morning and continuing until Thursday morning.
Environment Canada Meteorologist Trudy Kidd says around 30 to 50 millimetres is possible.
"There's a chance it could be even higher than that, particularly in thunderstorms, because we are also expecting thunderstorms on Wednesday," she says.
Kidd says this one could be heavy.
"We could have downpours, especially in thunderstorms, and so people are going to want to take their time on the roads," she says. "Don't be driving into any of those massive puddles because you don't know if you'll be able to get out of it."
Kidd says there is a possibility that they could issue rainfall watches or warnings as the storm approaches.
"With the thunderstorm potential tomorrow, we could be seeing thunderstorm watches and warnings tomorrow. So that's not something we'll see today, more so tomorrow when there's more certainty as to how the weather is shaping up," she says.
Localized flooding in low-lying areas is also possible.