A Yellow Heat Warning is in effect for Milton, Ontario, as the region enters its second major heat event of summer 2026. Environment Canada says daytime highs could reach 37°C, with humidex values making it feel like 38 to 45 through midweek.
Tuesday, July 14, is expected to be the hottest day. Current readings already show 31°C under clear skies and a feels-like of 35°C, according to The Weather Network. That is well above Milton’s mid-July average high of 26.7°C.
Overnight lows will provide little relief, dipping only to around 20 to 24°C. The UV index is rated as High, so residents spending time outside should take extra care to stay hydrated and limit sun exposure.
The heat also brings a health risk from wildfire smoke drifting into southern Ontario from Quebec. Environment Canada warns that air quality could get worse during the heat event, adding strain for those with breathing problems.
The current warning follows a similar heat wave near Canada Day. Tuesday’s peak could challenge records across the Greater Toronto Area, with some forecasts suggesting highs between 37°C and 40°C for nearby Toronto. The heat warning is expected to end either Wednesday evening or Thursday evening.
