Feels like 30? May heat finally reaches southern Ontario this weekend
Southern Ontario to see some well-timed warmer weather for the upcoming May long weekend. Summer-like temperatures are on the way, and for some, a humidex in the 30s!
Warmer weather is on the way for southern and eastern Ontario this weekend as a ridge of high pressure builds over the Great Lakes.
This pattern will raise temperatures into the 20s, with some areas nearing the 30°C mark by late Sunday into Monday.
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Temperatures take a major climb across southern Ontario Sunday and Monday
A system moving from the U.S. into northern Ontario Sunday night will bring a warm front over southern and eastern parts of the province.
Southerly winds combined with Gulf of Mexico moisture will drive temperatures to their peak.
Inland areas, particularly southwest Ontario, will feel the warmth the most, with high 20s expected in areas like London and Niagara, and forecast highs near 30°C for Windsor and the Sarnia region.
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By Tuesday, humidex values up to 30 will extend from Ottawa through Toronto to Windsor.
However, a cold front from the same system will break the heat, bringing rain and the potential for thunderstorms. Details around timing and intensity of the storms remain uncertain, but rain is expected.
Regardless, the warming trend is on track, offering southern Ontario a summer-like weekend before a shift in the pattern early next week.
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Don't underestimate the strength of the spring sun
Despite the cool start to spring and fewer sunny days overall, UV exposure can still be underestimated during the season. In contrast to summer, where warm temperatures often prompt the use of sunscreen and protective clothing, the cooler spring air may lead to a false sense of security.
With temperatures forecast to climb into the high 20s or even approach 30°C for the first time this season in some areas, it is crucial to stay mindful of sun protection. Pay close attention to the UV index and take appropriate precautions, including wearing sunscreen, protective clothing, and sunglasses.
Remember, UV exposure isn’t dependent on the temperature—it can remain high on clear days regardless of how it feels outside. Being prepared will ensure outdoor enjoyment while minimizing the risk of sunburn.
A cooler weather pattern is forecast to develop around the start of June and persist into the month.