Rainfall up to 50 mm and thunderstorms expected in parts of the north

A series of weather alerts are in effect Thursday in northern Ontario from the along the north shore of Lake Superior to both the Manitoba and Quebec borders.

Northwestern Ontario could see up to 50 millimetres of rainfall following two rounds of showers and thunderstorms, Environment Canada said.

"The first round will taper off this morning. The second is forecast to begin this evening and taper off Friday morning," the alert said.

"There is considerable uncertainty regarding the rainfall amounts. At this point in time, rainfall amounts in the 30 to 50 mm range are expected, with higher local amounts possible for areas that receive thunderstorms. Please stay tuned for updates."

The problem is the ground is already near saturation with little ability to absorb more rain, Environment Canada said in the rainfall warnings.

"Localized flooding in low-lying areas is possible. Avoid driving through water on roads. Even shallow, fast-moving water across a road can sweep a vehicle or a person away. Don't approach washouts near rivers, creeks and culverts. Keep children and pets away from creeks and river banks."

Special weather statements are issued for the Marathon and Nipigon areas east, where rainfall amounts of 20 to 40 millimetres are expected by Friday morning.