It’s official: while spring struggled to deliver consistently warm weather (May 2025 in Montreal could end up being the least sunny month in over half a century), a wet and humid summer is expected across the province.
According to a report by the Weather Network, Montreal should expect warm, humid temperatures (especially at night) with a few periods of extreme heat, including the city’s first heat wave before Canada Day.
A central North American heat dome will contribute to stormy conditions in Quebec, triggering uncomfortable humidity overnight and violent storms with heavy winds, hail and tornados.

Above normal precipitation is forecasted across southern and eastern Quebec, with frequent thunderstorms and risk for tropical remnants—the remnants of one or two tropical systems bringing significant rainfall to parts of the province.
Higher humidity should keep evening temperatures warmer than usual and contribute to more frequent showers and thunderstorms, with a risk of strong to severe storms and torrential downpours.
Keep an eye on the city’s air quality due to hazy smokey skies from distant wildfires.
And just when you think you can’t handle the humidity, occasional cold fronts are expected to deliver periods of cool weather.

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