Montreal's under another extreme heat warning — Here's how long the sticky weather will last

Temps will feel like 40°C and overnight relief isn't looking great

People walking under misting system to cool off during heatwave in Montreal.

The forecast calls for daytime highs above 30°C and humidex values near 40, making it another tough stretch for anyone without AC.

Marc Bruxelle| Dreamstime
Senior Writer

If it feels like Montreal's had more sweaty weather stretches than dry ones this summer, you're not wrong. In fact, at this point, it's getting hard to keep track.

Now, Montreal is back under another extreme heat warning, with the latest alert issued early Thursday by Environment Canada. The forecast calls for daytime highs above 30°C and humidex values near 40, making it another tough stretch for anyone without AC. And don't expect much relief after sunset, as overnight lows will stay above 20°C, which is considered "uncomfortable" by the agency's standards.

The heat warning is in effect until Friday for Montreal, Montérégie, and Lanaudière, though the muggy weather could hang around longer depending on how the forecast evolves.

"Take action to protect yourself and others," Environment Canada said in its notice. "Extreme heat can affect everyone's health."

Hydration, shade, and checking in on older or isolated people are all recommended — as is avoiding outdoor activities during the hottest parts of the day. If your living space is too hot, officials suggest heading to a cooler public space like a library, community centre, or shaded park. And yes, never leave people or pets in parked vehicles.

Here's what the next few days in Montreal are looking like:

  • Thursday, July 24: Mainly sunny, high of 33°C, humidex 40. Risk of thunderstorms overnight.
  • Friday, July 25: Showers in the morning, high of 27°C, humidex 35.
  • Saturday, July 26: Sunny and 28°C.
  • Sunday, July 27: Sunny and 31°C.
  • Monday, July 28: Sunny and 33°C.
  • Tuesday, July 29: Chance of showers, high of 29°C.
  • Wednesday, July 30: A mix of sun and cloud, high of 25°C.
While Friday's rain should help cool things off, three out of the next six days are expected to feature daytime highs exceeding 29°C.

You can find updates and tips from Environment Canada at weather.gc.ca.

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  • Al Sciola
  • Born and raised in Montreal, Al Sciola is a Senior Writer for MTL Blog. With a background in covering sports and local events, he has a knack for finding stories that capture the city’s spirit. A lifelong Canadiens fan and trivia enthusiast, Al spends his downtime sipping espresso and trying out new recipes in the kitchen.

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