Heat warning
Environment Canada has issued a Yellow Heat Warning for Chatham-Kent, Ontario, as of 5:14 AM EDT Tuesday, July 14, 2026. Temperatures are expected to reach 30–37°C with overnight lows of 20–25°C, and humidex values between 38 and 45. Today marks the peak of the heat event, with highs near 37°C possible in southwestern Ontario, the Greater Golden Horseshoe, and eastern Ontario. The heat is expected to ease tonight in central and northeastern Ontario but persist into Wednesday or Thursday across southern Ontario. Deteriorating air quality is also expected, with the Air Quality Health Index potentially reaching high-risk levels.
The warning urges people to check on older adults, those living alone, and other vulnerable individuals multiple times a day. It outlines signs of heat exhaustion (headache, nausea, dizziness, thirst, dark urine, fatigue) and heat stroke (red/hot skin, confusion, altered consciousness) — the latter being a medical emergency requiring a 911 call. Recommended precautions include drinking water regularly, closing blinds, using air conditioning or fans, seeking out cooling centres if needed, scheduling outdoor activity for cooler hours, wearing light clothing, and never leaving people or pets in parked vehicles. The public is asked to keep monitoring Environment Canada updates and can report severe weather via email or social media using #ONStorm.
Today – July 14, 2026
Clearing this morning. Wind becoming west 30 km/h this morning. High 35. Humidex 43. UV index 10 or very high.
Tonight
Clear. Wind southwest 30 km/h becoming light late this evening. Low 23.
Wed, 15 Jul – Sunny in the morning and early in the afternoon then a mix of sun and cloud with 40 percent chance of showers in the afternoon. Risk of a thunderstorm in the afternoon. High 33. Humidex 40. UV index 10 or very high. Night – Cloudy periods. Low 21.
Thu, 16 Jul – A mix of sun and cloud with 30 percent chance of showers. High 32. Night – Cloudy periods with 30 percent chance of showers. Low 20.
Fri, 17 Jul – Cloudy with 30 percent chance of showers. High 31. Night – Cloudy with 40 percent chance of showers. Low 20.
Sat, 18 Jul – Cloudy with 30 percent chance of showers. High 30. Night – Cloudy periods. Low 17.
Sun, 19 Jul – A mix of sun and cloud with 30 percent chance of showers. High 28. Night – Cloudy periods with 30 percent chance of showers. Low 17.
Mon, 20 Jul – A mix of sun and cloud with 30 percent chance of showers. High 28.
