Grey Bruce is under a rainfall warning Tuesday.
Environment Canada says heavy rain is expected at times as showers or isolated thunderstorms move across the region while a cold front approaches from the west.
Forecasters say total rainfall amounts of 50 to 60 millimetres is possible.
According to Environment Canada, the rain event will likely end this afternoon for areas near Lake Huron, and late this evening or overnight for areas east of Georgian Bay.
“Heavy downpours can cause flash floods and water pooling on roads,” the Environment Canada advisory says. “Localized flooding in low-lying areas is possible.”