Guelph is kicking off the week with mainly sunny skies and a comfortable 24 degrees on Monday, but residents should brace for a shift toward sticky, stormy weather over the coming days. Environment Canada reports no current alerts for the city, though the forecast warns of rising humidity and daily thunderstorm risks starting Tuesday.
Conditions will heat up quickly, with temperatures climbing to a high of 28 degrees on Tuesday and the humidex making it feel closer to 36. The chance of precipitation sits at 90 percent, according to The Weather Network’s seven-day forecast, with thunderstorms expected to develop in the afternoon. Storm activity is predicted to begin in the southwest, along the Huron shores, and stretch into cottage country before expanding to the Greater Toronto Area by evening.
The muggy pattern holds through Thursday, with daytime highs hovering around 28 or 29 degrees and humidex values reaching the high 30s. Thursday is shaping up to be the warmest day, with a feels-like temperature near 38. Friday will bring some relief, with a high near 26 degrees, though the risk of thunderstorms may persist. The warm, humid air mass moving across the province will keep humidity levels elevated through midweek. In Guelph, June humidity typically averages around 71 percent.
Historically, June is Guelph’s wettest month, averaging 99 millimetres of rain, and this week fits that pattern. While Monday offers ideal conditions for outdoor plans, residents should keep rain gear close and stay alert for changing skies starting Tuesday. Those working or playing outside are urged to take precautions against the heat, as humidex readings will make it feel much hotter than the actual temperature. Health officials recommend drinking plenty of water, seeking shade, and checking on vulnerable neighbours.
Although no heat warnings are in place as of Monday, Environment Canada issues heat warnings when two or more consecutive days are expected to reach 31 degrees or higher with warm overnight lows, and/or when humidex values of 40 or more are forecast. Forecasters will continue to monitor conditions and issue alerts if the situation escalates. For now, Guelphites can expect a week of shifting weather—pleasant starts giving way to humid, unsettled afternoons.
