The first official day of spring in southern Ontario started out foggy, but that soon gave way to clear skies, sun and yet another record-high temperature in Toronto.

Toronto hit 20 C by 3 p.m. Tuesday, setting yet another record-high temperature.

The previous record high for March 20 was 18.3 C, which was set in 1976.

The first official day of spring began under a blanket of dense fog Tuesday morning, prompting Environment Canada to issue a weather warning for drivers to take precautions while on the road.

Environment Canada issued a special weather statement for communities along the shore of Lake Ontario including Toronto, Mississauga, Hamilton and the Niagara Region.

The weather agency said patchy, dense fog had developed Tuesday morning, cutting visibility down to 200 metres in some places and leaving others in a complete blanket of hazy darkness.

The fog patches were expected to dissipate through the morning and give way to a clear, sunny day with an afternoon high of 23 C.

Monday, the last official day of winter, set a new record-high temperature as southern Ontario's warm spell continued into another week.

The temperature in Toronto topped out at 22.8 C, according to Environment Canada.

That beats the previous record for March 19 of 19.1 C, which was set in 2010.

The average high temperature for this time of year is 4.7 C and the average low is -4.4 C.

The good weather is predicted to continue into the week, with a high of 26 C on Wednesday and a high of 25 C on Thursday.

Environment Canada predicts rain will move into Toronto by the end of the week, but temperatures will remain unseasonably high.