Ontario's weather this week could hit 30 C in some spots — but it's not where you think

Ontario's weather is becoming harder to predict!

Ontonians enjoying sunny weather in Grange Park in downtown Toronto.

Ontario's latest weather forecast splits the province in two.

Vadim Rodnev | Dreamstime
Writer

Is it hot enough to hit up a patio, or should you be cozying up inside with a good book? That depends on where you are in Ontario right now, because the province is divided when it comes to weather this week.

According to the latest forecast from The Weather Network, while southern Ontario is dealing with clouds, cooler air and an on-again, off-again relationship with the rain, it's an entirely different story up north.

In a surprising twist for mid-May, temperatures soared into full-on summer mode in parts of northwestern Ontario over the weekend.

TWN revealed that Fort Frances hit a scorching 34.1 C on Sunday, with Atikokan close behind at 31.9 C. And that heat isn't going anywhere fast — more 30-degree days are on the way for the north.

This flip-flop in weather patterns is definitely not the usual spring setup. Toronto typically sees highs around 19 C this time of year, while northern spots like Moosonee sit closer to 13 C. But thanks to a warm front parked over the north, some areas feel more like July than May, with temperatures running 10 to 15 degrees above average.

Meanwhile, in the south? Not so lucky. A sluggish low-pressure system drags showers across the GTA and beyond, keeping temperatures a bit cooler than usual, with wet spells popping up throughout the week.

Rain chances go up on Tuesday, especially in southwestern Ontario, where scattered showers and even a cloudburst or two of thunder could show up. But don't worry — no severe storms are expected. Expect about 5 to 10 millimetres of rain to fall on Wednesday.

The showers will likely miss areas north of Toronto, so you might want to head up to the cottage if you're trying to dodge the drizzle.

By Friday, the breeze off Lake Ontario should calm down, letting temperatures rebound. Just in time for the long weekend, right?

Well... sort of. We're looking at a warm start, but here's a heads up: The forecast hints at a bump in the road with a chance for rain and cooler air making an appearance at some point over the weekend.

So maybe keep that umbrella and the sunscreen handy — Ontario can't seem to pick a lane right now.

This article's cover image was used for illustrative purposes only.

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  • Originally from Ireland, Tomás Keating is a Toronto-based Contributing Writer for Narcity. After graduating with a Masters in Journalism from the University of Galway in 2019, Tomás utilized his passion for news, current affairs, pop culture and sports as a digital journalist before relocating to Toronto in 2024. In his spare time, Tomás loves exploring the city, going to the cinema and playing Gaelic football with his local GAA club in Toronto.

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