Summer wants you to know it's not over just yet, as Toronto is experiencing record-breaking temperatures Wednesday and could be hit by severe thunderstorms.

The temperature rose to 34 C Wednesday afternoon, breaking the previous record for Sept. 5 of 31.7 C, which was set in 1945.

But with the humidity that's been blanketing the city in recent days, the temperature feels more like 43.

"It looks like it's going to be a very hot and humid day, not just across the GTA, but across much of southern Ontario," Mark Schuster, senior meteorologist with Environment Canada, told CBC Toronto early Wednesday morning.

Schuster attributed the day's heat and humidity to "a strong southwest flow of warm and humid air" from the United States.

While today will be "a very uncomfortable day," Schuster said, particularly for people living without air conditioning, the heat is expected to be "short-lived."

Severe thunderstorm watch in effect

Meanwhile, Environment Canada says conditions are favourable for the development of severe thunderstorms that may be capable of producing strong wind gusts, large hail and heavy rain.

"Severe thunderstorms are expected to develop this afternoon and end this evening," the federal weather agency said.

"These thunderstorms will be generated in the warm, humid airmass ahead of a cold front. This front will cross the regions tonight."

The agency says strong wind gusts can toss loose objects, damage weak buildings, break branches off trees and overturn large vehicles.

People are reminded that severe thunderstorms can produce tornadoes and heavy downpours can cause flash floods and water pooling on roads.

A cold front will move in Wednesday night and bring with it temperatures that are unseasonably low.

Thursday and Friday should see temperatures in the low-to-mid 20s, but Saturday's forecast high is 18 C, while Sunday's is 15 C.

That trend should last for about seven days, Schuster said, "but there is an indication that, as you look out ahead toward the middle of the month, it does look like temperatures may start to go above normal once again."