After a short break from the stifling heat that swept much of the region earlier this month, temperatures are expected to go back up.
Environment Canada has issued a heat warning for Windsor-Essex, Leamington, and Chatham-Kent.
Forecasters say a hot air mass is expected to come from the American mid-west on Friday.
Temperatures over the weekend are expected to stick to the low 30s, while humidex values are expected to reach the low 40s. The night will provide little relief, as the lows are expected to hover around 20 C.
The heat wave isn't expected to last too long. Environment Canada says a cold front is expected Monday night, which will lower the level of humidity.