Environment Canada has issued a special weather statement.
A weak disturbance is bringing snow and rain to most of Southern Ontario today.
A stronger, low pressure system is expected to energy from Colorado and affect the area Wednesday through Thursday.
The track of the storm is uncertain but significant snow is possible from Lake Huron and Georgian Bay across Lake Simcoe and into Eastern Ontario.
Motorists should be prepared for a return to hazardous winter driving conditions this week, especially in areas that receive freezing rain or snow.