Environment Canada says Toronto is under a frost advisory for Wednesday night into Thursday morning as temperatures are expected to drop to around the freezing mark.
The weather agency noted some plants may be damaged due to the frost and warn residents to cover up plants.
“Frost advisories are issued when temperatures are expected to reach the freezing mark during the growing season, leading to potential damage and destruction to plants and crops,” Environment Canada said.
Some areas closer to Lake Ontario may remain above the freezing mark, Environment Canada said.
The drop in temperature comes just two weeks after Toronto saw unusual summer-like temperatures in the mid to high 20s.
Parts of southern Ontario are also expected to see a month’s worth of rain over a few days starting Friday.
The Windsor area is also under the same advisory as Toronto.