Today's temperature earlier beat a 73-year-old record for this date as the hot and humid weather continues for another day.

The mercury hit 33.9 C at Pearson International Airport at 3 p.m. on Wednesday but it felt closer to the low 40s with the humidity.

The previous record for this date was 31.7 C and was set back in 1945. The average daytime high for this time of year is 23 C.

In advance of the scorching conditions Environment Canada has issued a heat warning for parts of the GTA, including Hamilton and Niagara Region, though the warning has not been extended to include Toronto at this point.

Severe thunderstorm warnings were issued for parts of the GTA and much of southern Ontario but the advisories have since been downgraded to a watch.

TDSB taking steps to keep students comfortable

The heat wave has renewed concerns about the temperature inside unairconditioned classrooms as student return to school this week.

TDSB spokesperson Ryan Bird said staff “do their very best” to keep students cool.

Measures, Bird said, include closing blinds, running fans, relocating students to cooler areas of the building, and reducing strenuous activity.

He added that the board in the process of installing cooling centres in all schools that don't have full-building air conditioning. The cooling centres would be located in large areas, including gyms and libraries.

"It is just too expensive to install full-building air conditioning in all the schools that don’t currently have it," he said, adding that the price tag would be close to $750M.

The TDSB will be installing cooling centres at about 80 schools each year until the project is complete.

The situation also garnered the attention of Marit Stiles, the education critic for the Ontario NDP, who used today’s hot and humid weather to highlight a need for funding to address the $15-billion capital repair backlog at 4,900 of the province’s publicly funded schools.

Stiles urged Premier Doug Ford’s government to reinstate the $100-million in funding for school repairs that was previously promised by the Wynne government, which would have been funded under the cap-and-trade system, a program Ford has cancelled.

“In the Toronto District School Board alone, we have a $4-billion capital repair backlog. That means leaky rooves. That means boilers that need replacing and it means that things like air conditioning in our classrooms bump down the list of priorities every year,” Stiles said at a news conference outside Clinton Junior Public School in Toronto on Wednesday afternoon.

“Students and staff- teachers, educators, janitors, are sweltering in classrooms this week… our students deserve better.”

In a written statement released Wednesday, Education Minister Lisa Thompson said the safety of students is a top priority for the Ford government.

"For the 2018-19 school year, school boards will receive up to $1.4 billion from the Ministry of Education in maintenance and repair funding," she wrote.

"We have previously committed to covering the costs incurred by school boards who have entered into contractual agreements for capital work, on or before July 3, 2018, within the Green House Gas Reduction Fund. School boards may also use their existing School Renewal Allocation funding to install new air conditioning systems in existing schools."