Montreal’s weather will feel like 41°C Tuesday — Here’s when temps will finally cool down

<img src="https://www.mtlblog.com/media-library/kids-cooling-off-in-the-water-basins-of-esplanade-of-place-des-arts-during-a-hot-day.jpg?id=61448655&width=1200&height=800&coordinates=132%2C0%2C132%2C0"/><br/><br/><p>Montreal is starting the week with a wall of heat, and it's only going to get hotter before it breaks. The city remains under a <a href="https://weather.gc.ca/en/location/index.html?coords=45.529,-73.562" target="_blank">severe heat warning</a>, with weather experts at <a href="https://www.mtlblog.com/tag/environment-canada" target="_blank">Environment Canada</a> calling for dangerously high temperatures through Tuesday.</p><p>Today's forecast is already pushing summer to the limit. Folks on the island can expect sunny skies, a high of 34°C and humidex values around 40°C. Overnight, it will only cool to about 22°C, meaning little relief before Tuesday's peak heat hits.</p><p>Tomorrow will be the worst of it, with highs again near 34°C but feeling closer to 41°C once humidity is factored in. Even the overnight low is expected to hover around 25°C, keeping the city in a prolonged heat spell.</p><p>The good news is that Wednesday should finally bring much-needed relief. A system of showers and cloudy periods will drop the high to 26°C and the low to 19°C, making it the first time in days the temperature dips below 20°C. The rain should also help ease the heavy humidity that's been hanging over the city since the weekend.</p><p><strong>Heat warning tips</strong><br/>In the meantime, though, Environment Canada is reminding Montrealers to take precautions during the extreme heat:</p> <ul> <li> Drink water often, even before you feel thirsty</li> <li> Check on vulnerable people like seniors and those living alone</li> <li> Plan outdoor activities for cooler times of the day</li> <li> Wear lightweight, light-coloured clothing and a wide-brimmed hat</li> <li> Never leave children or pets in parked cars</li> </ul> <p><strong>Montreal forecast</strong></p> <ul> <li> <strong>Monday:</strong> Sunny, high 34°C, humidex 40, low 22°C</li> <li> <strong>Tuesday:</strong> Sunny, high 34°C, humidex 41, low 25°C</li> <li> <strong>Wednesday:</strong> Showers and cloudy periods, high 26°C, low 19°C</li> <li> <strong>Thursday:</strong> Sunny, high 27°C</li> <li> <strong>Friday:</strong> Sunny, high 26°C</li> </ul> <p>You can get the latest updates from <a href="https://weather.gc.ca/en/location/index.html?coords=45.529,-73.562" target="_blank">Environment Canada's website</a>.</p><p><em>Love this? Check out our <a href="https://www.mtlblog.com/notices/" target="_blank">MTL Blog noticeboard</a> for details on jobs, benefits, travel info and more!</em></p><p><em>AI tools may have been used to support the creation or distribution of this content; however, it has been carefully edited and fact-checked by a member of MTL Blog's Editorial team. For more information on our use of AI, please visit our <a href="https://www.mtlblog.com/editorial-standards" target="_blank">Editorial Standards page</a>.</em></p>

mingooland August 11, 2025

2 min read