UPDATE, Monday, June 23, 2025: The City of Montreal issued a message this morning about the Montreal heat wave, and the measures they are putting in place to safely get through the upcoming heat wave: opening hours of swimming pools, water parks and air-conditioned areas will be extended; bottled water will be distributed to homeless people, and an automated call will inform vulnerable people identified in certain sectors. The city also cautioned Montrealers to drink plenty of water (don't wait until you're thirsty!), cool off by taking a bath or going to an air-conditioned location when you can, avoid intense physical exertion, wear light clothing, and above all, check on your loved ones, elderly neighbours, or any vulnerable person around you. Finally, the city issued a reminder that libraries, recreation centres and swimming pools are open and air-conditioned.
Get ready: the first Montreal heat wave of summer 2025 is about to hit the city.
With temperatures already reaching into the mid-30s, sweltering humidity from the recent wet weather will make it feel even hotter thanks to a humidex in the mid 40s.
The summer 2025 forecast predicted a wet, humid summer in Montreal, and now we’re in it.
Starting on Sunday, Monday may see temperatures in Montreal rise up to 46 degrees celsius.
The extreme heat event called a "Bermuda High" will last over three days.
No better time to hit the beaches in and around Montreal, not to mention the outdoor pools, tree-lined parks and shady hiking areas.
What is a Bermuda High?
According to an Environment Canada meteorologist, this three-day heat event is called a Bermuda High, due to a semi-permanent subtropical area of high pressure that is further north than usual.
It’s time to check on your air conditioning: the southern air that is circulating further north will feel oppressive, and thanks to the abundant precipitation we’ve had over the past months (40 percent more than usual), the moisture will compound with the heat making it feel like 40 degrees celsius (or more).
When will the heat wave hit Montreal?
According to the Weather Network, things will really start to heat up on Sunday.
Here’s what to expect:
Sunday, June 22: Expect a high of 30 degrees celsius that will feel like 40 degrees celsius
Monday, June 23: The heat will reach 34 degrees celsius with a humidex soaring to 46 degrees celsius
Tuesday, June 24 : The heat will hover around 33 degrees celsius and feel like 44 degrees celsius
Why is Canada having heat waves?
As greenhouse gas levels rise and drive global climate change, Canada is heating up at nearly twice the global average.
With hotter springs and summers, we’re seeing earlier snowmelt, more extreme heat waves, and ideal conditions for wildfires to spread.
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