Adedokun Waliyu 
A meteorologist with Environment Canada is warning Christmas Eve travellers to slow down on the roadways as dense fog hovering across Ontario could cause near zero visibility.
The weather agency has issued fog advisories for most parts of the province, starting from Windsor in the southwest to the Niagara and Kawartha Lakes areas in the northeast.
Meteorologist Sham Willie says the fog is expected to dissipate in the south by midday today and is forecast to return in eastern Ontario by Sunday night.
He says moisture trapped in the lower levels of the atmosphere is causing the cloudy conditions and low visibility.
Environment Canada says fog is not unusual during cold weather.
Willie adds Ontario can also expect to see above-average but not record-breaking temperatures on Christmas Eve and Christmas Day.
