A Colorado low that dumped up to 4 inches (10 cm) of snow in the Sarnia area overnight was moving east toward the Greater Toronto Area Tuesday.
Precipitation changed from snow to some freezing rain and then straight rain with the temperature expected to reach 5 C (41 F).
Sarnia streets were mainly clear and wet with some slushy sections while side roads were more snow covered.
Residents are asked not to park vehicles on the streets to facilitate the city's plowing and salting operations.
Lambton OPP Constable Travis Parsons says drivers are reminded to adjust to changing weather conditions.
"Slow down, stay alert and stay in control," says Parsons. "These simple steps will go along way in reducing the number of winter related collisions on our roadways."
Environment Canada's weather advisory was still in effect at noon Tuesday.
As the storm system moves through, south-southwesterly winds will develop gusting to 80 km/h.