TORONTO, Ont. – Environment Canada had issued a special weather statement for the Greater Toronto Area warning of the possibility of heavy fog, Wednesday morning.

The special weather statement is also in effect for other areas in southern and eastern Ontario, including Barrie, Orillia, Parry Sound, Muskoka, Windsor, Sarnia, London, Niagara, Hamilton, Waterloo, Kingston, Peterborough, Ottawa and Cornwall.

The weather agency said although the fog is expected to lift mid-morning, visibility could be near zero before that happens.

Drivers are urged to be extra careful on the roads.