Heat warning starts Friday for Windsor-Essex and Chatham-Kent
Humidity will make it feel as warm as 42 C
It's going to feel much hotter starting Friday.
Environment Canada says a hot and humid tropical air mass will affect southwestern Ontario through the weekend until at least Monday.
Afternoon temperatures are expected to reach the low to mid 30s, but will feel like the low 40s when factoring in humidity.
There won't be much relief overnight with temperatures hitting the low to mid 20s.
The weather authority advises to eat cool, light meals during this time and watch for the effects of heat illness, which include swelling, rash, cramps, fainting, heat exhaustion, heat stroke and the worsening of some health conditions.
People are also urged not to leave people or pets inside parked vehicles.
Environment Canada says slightly cooler and less humid conditions may arrive on Tuesday.