Snowfall warnings, and special weather advisories have been issued for most areas of the province.
A weather system moving from west to east is expected to dump five to 15 centimetres of snow across the region starting this morning. As much as 25 centimetres could fall on parts of the Greater Toronto Area.
Winds gusting to 50 kph are expected to blow the snow around, making for treacherous driving conditions.
And it will be cold, with frostbite inducing wind chill values of minus 20 C to minus 30 C.
Extreme cold warnings have been posted across northern Ontario. The forecast high today for Thunder Bay is minus 21 C with wind chill values ranging from minus 28 to minus 50.