Orangeville residents can expect a sharp rise in heat and humidity this week, with Environment Canada forecasting unseasonably warm temperatures and a chance of thunderstorms starting Tuesday. A warm, moist air mass moving into southern Ontario will push daytime highs well above the June average of 23°C, with the hottest conditions expected on Wednesday and Thursday.
Tuesday will bring a high of 29°C under increasing cloudiness, with a 40 percent chance of showers and a risk of afternoon thunderstorms. The humidity will make it feel much hotter, with a humidex reading of 37, according to Environment Canada. Winds will pick up from the south at 20 km/h late in the morning, and the UV index is forecast to reach 9, or very high, meaning sun protection is essential.
Thunderstorm activity is expected to begin Tuesday afternoon in southwestern Ontario and along the Huron shores before pushing into the Greater Toronto Area by evening and overnight. Environment Canada had not issued any weather alerts for Orangeville as of Monday afternoon, but residents should stay updated on conditions.
Wednesday and Thursday are set to be the warmest days of the week, with highs reaching 28°C and 30°C respectively. Both days carry a chance of showers, and the muggy conditions will persist. While the humidex on Tuesday comes close to Ontario’s heat warning threshold of 40, the criteria require two consecutive days of extreme temperatures or humidex, so no heat warning is currently in effect for Orangeville.
The sudden jump to midsummer heat after a cool spring can be tough for people who work outdoors, older adults, young children, and those without air conditioning. Signs of heat exhaustion include heavy sweating, dizziness, nausea, and muscle cramps. Anyone showing symptoms of heat stroke—hot dry skin, confusion, and high body temperature—needs immediate medical help.
More details on Ontario’s heat warning system and tips for staying safe in the heat are available from the Ontario Ministry of Health.
