Sunday marks the first day of summer, so what can we expect this season?

Kitchener's Victoria Park in the summer of 2026. (Dan Lauckner/CTV News)

Spring is going out on a soggy note.

The solstice arrives on Sunday, June 21 at 4:24 a.m., marking the first day of astronomical summer for the Northern Hemisphere.

It’s also the longest day of the year, with Waterloo Region expected to get 15 hours of daylight.

But before that happens, the forecast shows more rain, gusty winds and scattered thunderstorms before the end of the week. Heavy bursts of rain are expected to sweep through Waterloo Region on Thursday afternoon. Passing showers are possible through the weekend as well, but temperatures are expected to reach a daytime high of 22 degrees Celsius on Saturday, which is close to the seasonal average for the area.

Temperatures will continue to climb on Sunday, with an expected high of 24 degrees.

What we expect this summer in southwestern Ontario

Rob Kuhn, a meteorologist with Environment Canada, suggests temperatures will be slightly above average this summer.

“At this point, there’s no extended heat going on week after week, which can happen some summers. There’s no sign of that,” Kuhn said. “I think by the time June, July and August are done, we will see slightly above average temperatures.”

As for wet conditions, Kuhn thinks rainfall amounts will be slightly above average.

But, he added, the patten will be inconsistent.

“We already had one dry spell that lasted 11 days, which was completely rain-free,” he said. “I think we will see a number of these dry spells that could last one, two or even three weeks, that will be interrupted by bursts of showers and thunderstorms.”

Kuhn shared that, summer rain typically comes all at once instead of a day-long event.

“I wouldn’t be surprised if a day or two later on in the summer that we would get half a month to a month’s worth of rainfall all in one day from a couple of heavy showers and thunderstorms, and then the following week could be completely dry.”