Residents across London and Middlesex County could find themselves doing a lot of shoveling by Tuesday morning.
Environment Canada issued a snow squall watch for the region on Monday morning, as squalls over Lake Huron are expected to migrate south by Monday night. The watch was upgraded to a warning on Monday afternoon.
Between 10 to 20 centimetres of snow could fall before squalls tapper off Tuesday morning, the national weather agency said.
Roads could become difficult to navigate during the thick of the weather event with reduced visibility and slick conditions.
"Snow squalls cause weather conditions to vary considerably; changes from clear skies to heavy snow within just a few kilometres are common," said Environment Canada. "Visibility may be significantly and suddenly reduced to near zero. Surfaces such as highways, roads, walkways and parking lots may become difficult to navigate due to accumulating snow."
Drivers are advised to adjust their speeds accordingly and leave a safe distance between vehicles.
Eastern Lambton County and Watford are also under a snow squall watch, while a snow squall warning has been issued for Huron and Perth counties.
The dumping of snow comes as temperatures remain below the seasonal average daytime high of minus 2.3 C. Environment Canada's forecast calls for a daytime high Monday of minus 9 C, which will feel more like minus 21 because of the wind chill. Overnight, the temperature will fall to minus 15 C and feel like minus 19 C.
