Even hotter day in store for GTA

Southern Ontario faces at least another day of scorching heat, raising the possibility of record power consumption.

On Thursday, the humidex is going to make it feel like 44 or 45 C, according to CBC meteorologist Nick Czernkovich. "It's actually going to be a bit hotter … and more humid as well."

The temperature reached the mid-30s on Wednesday but felt more like the mid-40s when the humidity was factored in. By afternoon, air conditioners were on high — draining more than 24,600 megawatts of power from the grid — as Ontarians tried to beat the oppressive heat.

The peak power consumption on Wednesday was expected to come close to reaching the record of 27,005 megawatts.

Strangely, it appears Ontario's economy may be partly responsible for the province's ability to cope with the demand, which in the past has put a significant strain on the electrical grid.

Ontario's Independent Electricity Operator says the system can handle the job mainly because of a dramatic decrease in demand from Ontario's manufacturing sector, which shed nearly 300,000 jobs during the economic downturn.

Even so, Ontario Energy Minister Brad Duguid says the province is trying to encourage residents to conserve.

"We still have work to do to build what I would call a culture of conservation in the province," Duguid said. "We're determined to get there but it's going to take time to shift attitudes and to shift behaviour."

The City of Toronto — which issued an extreme heat alert on Monday — cancelled some asphalt and paving projects, concerned for the safety of construction workers.

But not all of the work on the city's roads stopped.

"Put it this way, if you can't handle the heat, you couldn't do it," said Paul Aparo, who was working on a paving crew.

Aparo said he takes in lots of liquids on days like these.

"I drink a lot of water, a lot of Gatorade, a lot of freezies, a lot of slushies, anything that's cold." 

Other outside workers say things still get done — just a little more slowly. 

"It's tough," said Mark Laurenti, who was working on a construction job in Regent Park. "We do what we can. It's not 100 per cent but we go as far as we can. We drink a lot of water. … When we get tired we slow down for 15 minutes and we continue." 

Ambulances in Toronto say they are receiving 51 per cent more complaints about breathing problems over the same time last year. EMS officials say fainting calls have jumped 39 per cent, and total call volume for ambulances is up about 13 per cent over 2009.

Environment Canada says residents will get a brief reprieve from the sky-high temperatures during a thunderstorm Friday, but the mercury will quickly climb again on the weekend.

Early forecasts show heat could envelop Ontario until August.