From Mostly Cloudy Skies to Showers and a Thunderstorm Risk by Wednesday

TORONTO – WEATHER REPORT – After a pleasant start to the week, Toronto’s skies are beginning to gray as a series of unsettled weather systems take hold across southern Ontario. While the city has avoided the scorching heat gripping much of the province’s north, it’s preparing for a soggy midweek stretch, complete with cooler temperatures and a chance of thunderstorms.

A Cloudier Pattern Moves In: Forecast Through Friday

At 7:00 AM EDT this morning, it’s a mild 14.1°C at Toronto Pearson International Airport under mostly cloudy skies. The dew point is 5.4°C, giving the air a crisp feel, and humidity is sitting at 56%. Winds are light from the east-southeast at just 4 km/h, while barometric pressure is at 101.8 kPa but falling—hinting at an approaching weather shift.

Today will see skies clouding over by late morning, bringing a 30 percent chance of showers into the afternoon. Temperatures will climb to a modest high of 19°C, accompanied by a UV index of 6, which is still considered high despite the clouds—so sunscreen should still be part of your daily outfit.

Tonight remains cloudy with the same 30 percent chance of showers and a mild low of 13°C.

Wednesday will stay overcast with a 40 percent chance of showers in the afternoon, along with the risk of a thunderstorm sneaking in by late day. Temperatures will climb to a slightly warmer 20°C, and the UV index will again hold at 6. Wednesday night will remain cloudy with a low of 14°C.

Thursday continues the same cloudy theme with a 40 percent chance of showers and a daytime high of 22°C. The night will bring increasing cloudiness and a low of 14°C.

Friday brings a better chance of more widespread rain, with a 60 percent chance of showers throughout the day and a high of 23°C. The night will feature cloudy periods and a mild low of 13°C.

Wardrobe Advice for Toronto’s Spring Mood Swings

Today is a day for layers—think a light jacket or hoodie and an umbrella tucked into your bag. With clouds and on-and-off showers in the forecast all week, keep the waterproof footwear handy, and don’t forget that even on cloudy days, the UV index is still high enough to warrant sun protection.

Historical Weather for May 13

Toronto’s record high for this date is 30.3°C, while the record low is a brisk 1.1°C. Today’s forecasted high of 19°C is on the cooler side of that spectrum, keeping things feeling like a traditional Toronto spring.

Toronto Weather Trivia

Did you know? Thanks to the moderating effects of Lake Ontario, Toronto often sees prolonged cloudy spells in the spring, especially when warm, moist air collides with cool lake breezes. This often leads to a few days of unsettled, humid, and muggy conditions—just like what’s on the menu this week.