Rainfall warnings are in effect across a large swath of Ontario, including Ottawa and Smiths Falls.
Environment Canada is forecasting significant rainfall over the next couple of days, due to a cold front and a moisture laden low pressure system out of the American midwest.
"We're basically getting like a months worth -- or more -- of rain in about 36 hours, so definitely quite the rainy stretch," says CityNews Ottawa Meteorologist Jill Taylor.
Showers and isolated thunderstorms are expected to continue until the weather system moves out of the region Friday morning. Rainfall amounts of 60 to 90 mm expected, with some areas exceeding 100 mm.
Localized flooding in low-lying areas is possible and heavy downpours can lead to flash floods and water pooling on roads.
Environment Canada suggests keeping children and pets away from creeks and river banks during these types of weather conditions.