News

Montreal weather: extreme summer 2025 forecast brings post-tropical cyclones and torrential downpours

A wet, humid summer is on its way to Montreal bringing severe storms and above normal precipitation.

Laura Osborne
Written by
Laura Osborne
Editor, Time Out Canada
Storm
Photograph: Shutterstock / Marc Bruxelle
Advertising

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.

Storm, Montreal
Photograph: Jason Arthur

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.

Storm, Montreal
Photograph: Jason Arthur

What is the summer temperature in Montreal?

Montreal averages 21ºC in July, with the warmest temperatures typically hitting around 26ºC in the afternoon.
At night, it cools down to about 16ºC, so a light sweater or cardigan is a good idea for evenings in the city.

RECOMMENDED:
Full guide to the best things to do in Montreal
Montreal's best pools to cool off in this summer
Best parks in Montreal

You may also like
You may also like
Advertising