Environment Canada is warning Ontarians to expect another round of dense fog Thursday morning.

Motorists contended with fog during their morning commutes Tuesday and Wednesday, as visibility was almost zero in some spots.

Dense fog is expected to develop again early Thursday morning.

On Wednesday, several crashes were reported during the morning drive.

Heavy fog was reported at highways 12 and 48 in Beaverton, where a tractor-trailer went into a ditch, Ontario Provincial Police said.

Airlines issue travel advisories

Because of the fog, airlines issued travel advisories warning of potential flight delays or cancellations.

Porter Airlines issued an advisory for Toronto, Sudbury, Timmins, Thunder Bay, Sault Ste. Marie and Chicago airports, urging customers to check their flight status before heading to the airport.

Air Canada warned flights at Pearson International Airport could be affected by “forecasted low ceilings, fog and reduced visibility and subsequent air traffic control restrictions.”

As for the rest of Wednesday, Ontarians can expect a pleasant day. Wednesday will be sunny with a high of 10 C. The normal high for Nov. 21 is 6 C.

Highs of up to 12 C are expected Thursday and Friday before the temperature drops off for Grey Cup weekend.

Environment Canada is predicting a high of just 2 C for Saturday and Sunday, in addition to a chance of snow flurries Sunday.

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