Hot and humid weather is returning to Windsor-Essex and Chatham-Kent.
Environment Canada has issued a heat warning for the areas.
Temperatures reaching 31 Celsius, combined with overnight lows near 21 C are expected for the next two days.
The forecaster says a hot and humid air mass from the Southern United States will move over the region beginning Tuesday and continuing Wednesday. Afternoon temperatures expected to in the low thirties both days. Minimum temperatures in the low twenties Tuesday night will provide little relief from the heat.
Humidex values in the upper thirties to near 40 are likely for both days.
A cold front sliding down from the north will bring this heat event to an end Wednesday night.
Health officials warn about the dangers for young children, pregnant women, older adults, people with chronic illnesses and people working or exercising outdoors.
They urge people to drink plenty of water even before you feel thirsty and stay in a cool place.
Never leave people or pets inside a parked vehicle.
Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.
Symptoms of heat-related illness may include: rapid breathing, dizziness or fainting, vomiting, rapid heartbeat, extreme thirst and decreased urination with unusually dark yellow urine.
If anyone has these symptoms, move into an air conditioned area and call a health care practitioner.