Hot and humid conditions will continue across much of southwestern Ontario on Sunday and Monday.
Environment Canada has issued a heat warning for Windsor-Essex, Chatham-Kent, London-Middlesex, as well as Elgin and Oxford Counties. Warnings were also issued for Listowel, Stratford, and Huron-Perth Sunday afternoon.
Daytime temperatures are expected to reach upwards of 30 C with humidex values ranging from 37 to 40.
The weather agency said warnings are issued when very high temperatures or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke, or heat exhaustion.
"Hot and humid air can also bring deteriorating air quality and can cause the Air Quality Health Index to approach the high-risk category," the warning read.
Environment Canada will continue to monitor the forecast and provide updates as needed.