Dense fog descended on much of southern Ontario on Thursday, posing hazardous driving conditions and affecting operations at airports.
Environment Canada issued fog advisories throughout the day, with parts of the Greater Toronto Area affected through the evening commute while the warning was lifted in other regions earlier in the day.
Toronto's Pearson International Airport said it reduced the flow of arriving flights to maintain safe operations amid the foggy conditions.
Billy Bishop Airport in downtown Toronto also warned travellers that fog and poor visibility could cause flight delays.
Environment Canada said drivers should slow down, watch for tail lights and be prepared to stop if visibility is reduced while driving.
Earlier in the day, the fog advisory had stretched from Belleville, Ont., to Woodstock, Ont., with near zero visibility in those areas.