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       A man sleeps on the sandy beach along Lake Ontario in the extreme heat in Toronto on July 19, 2019.

       Nathan Denette/The Canadian Press

       Environment Canada has issued heat warnings for parts of southern Ontario as temperatures soar.

       The warnings stretch from the Windsor area through Toronto and east to Durham Region.

       The agency says Monday’s daytime temperatures are expected to go as high as 34 degrees Celsius.

       Overnight temperatures are forecast to be lower at 21 to 25 degrees Celsius.

       The agency says a cold front is expected to move in on Tuesday evening, bringing showers and thunderstorms to the area.

       Heat warnings are also in effect for a portion of northeastern Ontario, including the city of Timmins.

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