Toronto has opened seven emergency cooling centres as part of its extreme heat alert response. (Dwight Friesen/CBC)

It will probably be a few more days before the GTA gets a break from the record-breaking heat.

The City of Toronto declared a heat alert on Monday — and then upped it to an extreme heat alert a day later.

The extreme alert will probably stay in effect for at least another day as daytime highs hover around 31 C.

According to Environment Canada senior climatologist Dave Phillips, a high-pressure system that started in U.S. has caused a heat bubble that stretches across Ontario and Quebec.

Phillips says some areas of Ontario have seen more hot days this week than in all of last summer.

"It is a little early," said Elaine Smyer who is the manager of emergency planning for the city, referring to the skyrocketing temperatures.

"A few years ago we did have a cooling centre opened on May 31, so we are early this year," she said.

Smyer said almost 300 people made use of the seven official cooling centres on Tuesday and the city is asking neighbours to check on those who might be vulnerable during the heat wave, "especially isolated adults and seniors who are at greater risk of suffering from heat-related illness," said a news release on the city's web site.

"Other at-risk groups include people with chronic illnesses, including mental illness, infants and young children, people on certain medications and those who are marginally housed or homeless," it said.

The Red Cross was also out Wednesday helping people in downtown Toronto stay cool, with volunteers handing out water bottles to people at Trinity Bellwoods Park.

Smyer says it's hard to predict is this is a preview of what summer in the city will be like.

"Some years we've gone without any extreme heat alerts called and others — I think the longest we've had was something like 18 days. So it's really hard to predict how many extreme heats we're going to get."

Phillips says Environment Canada models suggest the heat and dryness will continue and Toronto may get "too much summer."

With files from The Canadian Press