Eastern Canada Heat Wave: Latest Update (July 15, 2026)
A significant heat wave is affecting much of eastern Canada this week, particularly southern Ontario, southern Quebec, and parts of Atlantic Canada. Environment and Climate Change Canada has issued heat warnings for many communities as a strong ridge of high pressure settles over the region.
What to expect
- 🌡️ Southern Ontario
- Daytime highs: 30–35°C
- Humidex values: 38–44°C, with some areas potentially feeling even hotter.
- Warm nights (20°C or higher) will provide little relief.
🌡️ Southern Quebec
- Similar conditions, with temperatures climbing into the low to mid-30s.
- High humidity will make it feel considerably hotter.
🌡️ Atlantic Canada
- While not as extreme as Ontario and Quebec, inland areas of New Brunswick and Nova Scotia may reach the upper 20s to low 30s.
- Coastal communities, including Saint John, are expected to be somewhat cooler because of onshore winds and the Bay of Fundy, although inland humidity may still make conditions uncomfortable.
Other concerns
The hot, dry weather is also increasing wildfire danger across parts of Canada. Smoke from active wildfires may reduce air quality in some regions, especially if winds shift.
Staying safe
- Drink water regularly, even if you don’t feel thirsty.
- Limit strenuous outdoor activities during the hottest part of the day (roughly 11 a.m. to 4 p.m.).
- Check on older adults, young children, and anyone without air conditioning.
- Never leave children or pets in parked vehicles.
If you’re in Saint John, New Brunswick, the heat should be less intense than in Ontario or southern Quebec, but it may still feel quite warm and humid inland, with cooler temperatures returning near the coast.