A late‑April cold snap prompted a yellow‑level frost advisory for Toronto and several parts of the GTA, with Environment Canada warning that temperatures would dip to near- or below-freezing overnight into Friday morning.
The advisory was issued at 9:10 a.m. Thursday and applied to a wide stretch of southern Ontario.
It includes Toronto; the communities of Pickering, Oshawa, and the rest of southern Durham Region; the municipalities of Vaughan, Richmond Hill, and Markham; Hamilton, Mississauga, and Brampton; the towns of Halton Hills and Milton; the communities of Burlington and Oakville; and the broader Niagara Region.
Environment Canada says the impact level is moderate with high confidence in the forecast, noting that patchy frost is likely to form under clearing skies and cold overnight air.
Residents are being urged to cover vulnerable plants or bring potted ones indoors, especially in frost‑prone or low‑lying areas where temperatures can fall more quickly.
Despite the downside of it being this chilly in late April into early May, CityNews meteorologist Jessie Uppal says it’s not uncommon to see frost in the GTA during this time of year.
“Typically, we still experience frost through the last week of April and first week of May,” Uppal said. “Although this year, the end of April has been cooler compared to the last two years. In 2022, we had an even colder stretch of frosty nights in late April, 27, 28, 29, falling below the freezing mark.”
Cold pattern continues into weekend as May arrives
The frost threat follows a stretch of below‑seasonal temperatures across the GTA. The region is heading into a chilly start to May, with daytime highs struggling to reach the low teens and overnight lows repeatedly dipping toward freezing.
Thursday’s high is expected to reach only 11°C, with scattered showers lingering. Friday will be even colder, with a brisk northwest wind, a high near 10°C, a low around 1°C, and potential for flurries north of the city.
Most of the weekend should stay dry, with just a few chances of showers late Saturday, although temperatures will dip well below seasonal levels. Sunday will be drier but still cool, reaching a daytime high of 11°C.
More consistent double‑digit temperatures are expected to return next week, though rain remains in the forecast.
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