After a brief reprieve, the hot and humid weather is back across Ontario and parts of the Prairies.

Environment Canada has issued heat warnings across the majority of Ontario as well as southern Manitoba and parts of Saskatchewan.

Temperatures will peak around 37 C in parts of southern and eastern Ontario on Tuesday, with humidex values that could reach the mid-40s, according to a yellow heat warning from Environment Canada.

Overnight will provide few opportunities to cool off with low temperatures remaining above 20 C.

With the FIFA World Cup semifinals beginning Tuesday, many are expected to attend Fan Fest in Toronto as well as fill patios and bars to watch the game.

Dr. Howard Shapiro, Toronto’s associate medical officer of health, told Global News it’s important for people attending these outdoor events or participating in other outside activities to take precautions to avoid heat-related illnesses.

“If you’re going to be outside, wear light-colored, breathable clothing, wide-brimmed hats and be sure to protect yourself from the sun by staying in a shaded area or putting on sunscreen,” he said. “If you get a sunburn, that’s going to impair your ability to stay cool. And also make sure you have water.”

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When a heat wave rolled into Toronto between June 30 and July 4, Toronto Public Health recorded 39 emergency department visits for heat-related illness, including 15 visits on a single day.

Shapiro said heat-related illness is avoidable and cautions people who spend time outdoors to pay attention to how they are feeling.

“If people are able to take precautions, then you’ll avoid being one of those statistics,” he said. “But it’s a regular pattern.”

The city has also expanded its network of cooling centres for people without access to air-conditioned shelter.

While southern Ontario may be hot, parts of northern Ontario and southern Manitoba will carry the brunt of the heat wave.

Environment Canada has issued an orange heat warning for these areas where temperatures could reach up to 40 C with humidex levels making it feel like 45.

Seven communities across Manitoba set a new daily high temperature on Sunday, slashing decades-old heat records, according to Environment Canada.

The highest temperature (35.8 C) was recorded in Gretna, Man., a small community on the United States border. Records were also set in Carberry (34.7 C), Grand Rapids (32.9) and Portage La Prairie (35.7).

Environment Canada said record-setting temperatures are expected to continue throughout the day Monday before dropping to the low 30s or high 20s on Tuesday.

Parts of southeastern Saskatchewan are also under an orange heat warning with Environment Canada forecasting temperatures to exceed 32 C.

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