Environment Canada has issued a heat warning for most of southwestern Ontario, including all of Niagara.
Humidex values reaching 40 are expected.
The hot and humid weather will continue through Wednesday.
Maximum daytime temperatures near 31 degrees are generally expected through Wednesday with humidex values near or above 40. Overnight minimum temperatures will likely remain near 21 degrees providing little relief from the heat.
Scattered showers and thunderstorms are possible each day which could prevent maximum daytime highs reaching 31 every day in every area. However, maximum daily humidex values are still expected to be near 40 degrees.
A cold front is expected to move through Wednesday night bringing an end to the hot and humid weathe
And Niagara Region Public has issued an excessive heat alert starting today.
Niagara residents are advised to take extra precautions during episodes of extreme heat and humidity.
Signs of heat-related illness may include confusion, dizziness, nausea, muscle swelling, heart disturbances, and headache.
Some steps to minimize heat related illness include drinking plenty of fluids, and if you have to be outside, plan your activities during cooler parts of the day.
Any health condition that causes dehydration makes the body more susceptible to heat sickness. Consult your doctor if you feel signs of confusion, dizziness, nausea, muscle swelling, heart disturbances, and/or a headache.