A large swath of southern Ontario is under a freezing rain warning ahead of a system that’s expected to move in overnight.
The warning from Environment Canada, issued just after noon Monday, stretches from north of the Barrie area, south to the London area.
The Greater Toronto Area and the Niagara Region are included in the warning.
Global News meteorologist Anthony Farnell said wet snow mixed with freezing rain is expected to move in overnight into Tuesday morning.
He said the precipitation will generally be light with only a few millimetres expected.
“But any amount of freezing rain can be dangerous on untreated road surfaces,” he said.
“Areas away from Lake Ontario over slightly higher terrain will be most susceptible, especially bridges and overpasses.”
Temperatures will climb above freezing into the morning, so road conditions will quickly improve, he said.
Environment Canada said the precipitation will change to rain Tuesday morning or early afternoon, depending on the location.
“There may be a significant impact on rush hour traffic in urban areas,” the weather agency warned.
Meanwhile, later in the week, a “stronger system” is expected to impact southern Ontario, Farnell said.
It will move in on Thursday, bringing more mixed precipitation and the risk of freezing rain.