While the area was offered a brief reprieve from early summer’s heat wave, stifling temperatures are expected to return for a large portion of southern Ontario this weekend.
Environment Canada has issued a heat warning for Saturday and Sunday for an area that stretches from Peterborough to Windsor and includes Toronto, Hamilton, Niagara Falls, Kitchener, London, Guelph and Barrie.
The agency says that while daytime highs could rise to between 31 and 33 C, as humidex values could get as high as 40.

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There is not going to be much reprieve when the sun sets, as Environment Canada warns that overnight lows will only fall to around 21 to 25 C.
“Take action to protect yourself and others – extreme heat can affect everyone’s health,” the warning says. “Determine if you or others around you are at greater risk of heat illness.”
Environment Canada asks that people check in on older adults, those who live alone or other people who are at risk.
“Watch for the early signs of heat exhaustion in yourself and others. Signs may include headache, nausea, dizziness, thirst, dark urine and intense fatigue. Stop your activity and drink water,” Environment Canada warns.
“Heat stroke is a medical emergency! Call 9-1-1 or your emergency health provider if you, or someone around you, is showing signs of heat stroke which can include red and hot skin, dizziness, nausea, confusion and change in consciousness.”
Environment Canada said cooler temperatures are in the forecast for Sunday evening.
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