Milton is off to a sizzling start this week with clear skies and a high UV index prompting health officials to urge sun safety on Monday, July 20, 2026. Environment Canada forecasts sunny conditions with a high of 26 C, a humidex making it feel like 28, and a very high UV index of 9. By late afternoon, winds from the southwest will pick up to 20 km/h, adding a slight breeze to the summer heat.
The Weather Network reported mainly sunny skies and a temperature of 22 C around 5:00 p.m. Monday, with a feels like reading of 23 C and a high UV level. No weather alerts are currently in place for Halton Hills-Milton after earlier heat and air quality warnings tied to wildfire smoke were lifted earlier this month.
Environment and Climate Change Canada advises that UV index levels of 8 or more require limiting direct sun exposure, particularly between 11 a.m. and 3 p.m. when rays are strongest. Residents should wear UV protective sunglasses, seek shade, and reapply sunscreen every two hours or after swimming or heavy sweating. Unprotected skin can burn quickly under a UV index of 9.
The summer blast won’t last all week. Tuesday, July 21, brings cloudy skies with showers starting early in the morning and a risk of thunderstorms. Wind from the southwest at 30 km/h, gusting to 60 km/h, with a high of 24 C and a humidex of 32. The UV index drops to a moderate 3. Wednesday sees a mix of sun and cloud with a 30 per cent chance of showers and a cooler high of 22 C before sunshine returns Thursday and Friday with highs of 26 C and 28 C.
The UV index, now used worldwide, was created by Canadian scientists at Environment and Climate Change Canada in 1992 and adopted by the World Health Organization as an international program two years later, becoming a global standard in 2002. Historical July normals in Milton include a maximum of 26 C and minimum of 15 C, with sunrise at 5:56 a.m. and sunset at 8:55 p.m. Eastern Daylight Time.
