Rainfall warning issued for Toronto with up to 40 mm possible

CP24’s meteorologist Bill Coulter provides an update on weather conditions in Toronto and parts of the GTA.

Heavy rain could cause localized flooding in parts of the GTA over the next 48 hours with some areas expected to see more than half a month’s worth of precipitation over a 24-hour period.

Toronto is currently under a rainfall warning, yellow alert, and Environment Canada said the city could see between 20 and 40 millimetres of rain on Tuesday and Wednesday.

“A series of low pressure systems will lead to significant rainfall across parts of southern Ontario,” Environment Canada’s advisory read.

“Water will likely pool on roads and in low-lying areas. Don’t drive through flooded roadways. Avoid low-lying areas. Watch for washouts near rivers, creeks and culverts.”

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CP24 Meteorologist Bill Coulter said heavy periods of rain will begin at around midnight and will come in rounds.

“Because the ground is compact because of the cold season, we are looking at runoff which could create ponding and pooling and localized flooding through the day tomorrow,” Coulter said Tuesday.

“More than half a month’s rain is possible in some areas in less than 24 hours.”

He said Toronto sees about 70 to 80 millimetres of rainfall equivalent at Pearson every month.

The rain will move off to the east late Wednesday afternoon, Coulter said, bringing cold air with it.

“Once that rain clears to the east, cold winds will fire up and the temperatures are expected to return to wintery values,” Coulter said.

“Prepare for the risk of wintry precipitation for the end of the work week.”

He urged Torontonians to enjoy the mild temperatures while they last.

Toronto will see a high of 13 C on Tuesday. There will be a mix of sun and cloud before showers begin this afternoon.