Environment Canada is warning of three to six hours of freezing rain in Toronto and much of southern Ontario on Tuesday evening and into the night.

The freezing rain warning stretches from Kitchener-Waterloo to the Brockville area.

The weather service said precipitation ahead of a low-pressure system from Texas reached south-central Ontario early Tuesday evening.

"A prolonged period of freezing rain, about three to six hours, is likely for most of the … areas. Two to five millimetres of ice buildup is possible," the warning stated.

The freezing rain may change briefly to rain or snow before ending overnight in south-central Ontario.

Motorists should adjust their travel plans, according to the warning.