Heat wave to bring possibly record-breaking temperatures to start summer
Posted Jun 20, 2025 06:48:49 AM.
Last Updated Jun 20, 2025 11:09:21 AM.
Summer will announce itself with a four-day heatwave that is set to bring record-breaking temperatures to Waterloo Region.
The official start to the season comes at 10:42 on Friday evening.
Sunday’s forecasted high of 34 C could break a temperature record of 32.8 C set in 1923. Monday could reach highs of 35 C, again potentially breaking a 1923 record of 33.3 C.
Tuesday will cool down a touch to highs of 33 C, reaching up towards a 1952 record of 36.1 C.
“It’s overall very hot and humid,” said 570’s Meteorologist Jill Taylor. “Plan now to make sure you can get to a cool spot. If you have to work outdoors, especially, you’re going to want to be in the shade, take breaks, and just stay hydrated.”
Taylor added that temperatures should cool down as we head into Wednesday.
People will have to contend with some considerable humidity over that four-day stretch. Those mid-thirties temperatures will feel like upwards of 45 C with the humidex.
If you or someone close to you who is vulnerable to heat needs a place to cool down, there are public spaces available.
Libraries, community centres, and city halls are open to the public who needs to beat the heat. A full list of spaces can be found at www.regionofwaterloo.ca/en/health-and-wellness/.
