Environment Canada has issued a special weather statement for much of Southern Ontario, warning of the possibility of up to 10 centimetres of snow by Tuesday morning.
The warnings affect areas stretching from Windsor in the southwest up to Huron-Perth and Waterloo and into the Greater Toronto Area and the Golden Horseshoe.
The weather agency says a disturbance coming up from the United States will bring snow into southwestern Ontario beginning late Monday afternoon.
It's then expected to head east into the Golden Horseshoe region late Monday evening.
The agency says its latest indications suggest most regions could get five to 10 centimetres of snow and strong gusty winds are expected to produce local blowing snow.
Those who are travelling are advised to allow extra time due to accumulating snow and reduced visibility. The snow is expected to taper off from west to east Tuesday morning.