Area roads became so slick in spots Friday that even a snow plow slid off the road.
The plow and a few other vehicles were being pulled from the ditch and median on eastbound Hwy. 402 in the early afternoon, causing traffic slowdowns east of Longwoods Rd.
OPP are urging motorists to reduce their speed and driving according to the conditions.
Snow from a slow-moving storm system tracking across the lower Great Lakes is expected to continue into Friday evening with accumulations of 10 cm to 15 cm. (4-6 inches)
Environment Canada posted a special weather statement for Sarnia-Lambton and London-Middlesex while a snowfall warning was in effect in Chatham-Kent and Windsor-Essex where amounts up to 20 cm (8 inches) were forecast.
School buses were cancelled across Lambton-Kent Friday and both the Sarnia Sting at Kitchener and Sarnia Legionnaires at St. Thomas hockey games were postponed.
Meteorologist Geoff Coulson says more snow will fall over the weekend.
"We have another system on Saturday that may give a few more centimetres accumulation and then another one on Sunday coming out of the Texas Gulf Coast area with a fair amount of moisture with it," says Coulson.
Sunny skies are forecast for Monday with the temperature climbing above zero, at 3 C (37 F) on Tuesday.