The Parliament buildings are seen behind Drew Lander as he spends Victoria Day fishing and enjoying the warm weather in the Ottawa River in Ottawa. The city's medical officer issued a heat alert on Tuesday as temperatures were expected to hit above 30 C. (Pawel Dwulit/Canadian Press)

A heat wave that made Victoria Day feel more like Canada Day throughout Ontario is expected to continue on Tuesday, as record-breaking temperatures are expected in a number of cities, including Toronto and Ottawa.

Ottawa's medical health officer issued its first heat alert of the season for Tuesday and Wednesday, as Environment Canada is forecasting the temperature to hit 33 C on Tuesday, which would be a record for the month of May. The humidex for both days is expected to be over 36.

Toronto also issued its first heat alert on Monday, and is expecting temperatures on Tuesday to hit 29 C, a record for May 25.

Windsor was expecting a high of 29 C and while no humidex advisory was issued, the city decided to open its largest children's spray pad three weeks early.

During heat alerts, people are advised to stay cool and hydrated — and avoid strenuous activity through the mid-day hours. The elderly, infants and people with chronic health conditions are also advised to stay in a cool place.

Environment Canada said in a statement Tuesday that humidity drawn from the Gulf of Mexico is giving the heat in the province "an extra punch."

On Monday Northern Ontario was the place for record temperatures, with Chapleau, Geraldton, Timmins and Sault Ste.Marie all hitting or passing the 30 degree mark.

The hottest place in Canada on Monday was also one of the most unlikely: Kapuskasing hit a record high temperature of 34.6 C.

The average high in the northern town for May 24 is 18 C, according to Environment Canada.

The hot temperatures are expected to continue through to Wednesday for Northern and Eastern Ontario before cooling down to the mid-twenties on Thursday, while southern Ontario is expected to remain hot until the weekend.