Extreme heat warning issued across Southern Ontario for Father’s Day

Environment Canada has issued an extreme heat warning for Sunday in Southern Ontario as forecasts indicate humidex values will likely surpass 40 degrees Celsius.

The affected area extends through the following regions: Hamilton, Toronto, Dunnville, Caledonia, Haldimand, Elgin, Halton – Peel, Huron, Perth, London, Middlesex, Niagara, Oxford – Brant, Sarnia, Lambton, Simcoe, Delhi, Norfolk, Waterloo, Wellington, Windsor, Essex, Chatham-Kent, York and Durham.

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The alert was later extended to include the following areas: Algonquin. Bancroft, Bon Echo Park, Barrie, Orillia, Midland, Brockville, Leeds and Grenville, Burk’s Falls – Bayfield Inlet, Ottawa, Cornwall, Morrisburg, Dufferin, Innisfi, Grey, Bruce, Haliburton, Parry Sound – Muskoka, Peterborough, Kawartha Lakes, Prescott and Russell, Renfrew, Pembroke, Barry’s Bay, Simcoe, Delhi, Norfolk, Smiths Falls, Lanark, Sharbot Lake, Stirling, Tweed and South Frontenac.

Forecasts indicate temperatures are expected to reach 31 degrees on Sunday and Monday before a cold front arrives Monday night to provide relief.

Environment Canada reminds Canadians that it is never a good idea to leave people or pets inside a parked vehicle.

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People are urged to monitor themselves and loved ones for symptoms of heat stroke or exhaustion.

Symptoms include:

• High body temperature
• Lack of sweat
• Confusion
• Fainting
• Unconsciousness

Particular vigilance is recommended for children, seniors, individuals with pre-existing lung, heart, kidney, nervous system, mental health or diabetic conditions, outdoor workers as well as those who are socially isolated.

*With files from Global News’ Kirby Bourne