Grimsby and the rest of Niagara Region are under an air quality warning as wildfire smoke from northwestern Ontario drifts across the area. Environment Canada issued the orange-level alert on July 15, 2026, and it is expected to last through at least July 17.
The smoke has pushed the Air Quality Health Index to 10+, a very high risk level, in parts of the region including St. Catharines. Combined with an ongoing heat alert, temperatures are hitting 30 to 37 degrees Celsius, with humidex values making it feel like 38 to 45.
Niagara Region Public Health is urging everyone to stay indoors with windows shut and skip strenuous outdoor activities. The people most at risk include seniors over 65, pregnant individuals, infants, young children, folks with chronic health conditions, outdoor workers, and anyone without stable housing.
The smoke has already led to cancellations across the area. The nightly fireworks at Niagara Falls were called off on Wednesday, and outdoor sports in Thorold, including minor baseball and soccer, were scrapped. Niagara-on-the-Lake has put a burn ban in place immediately.
The source of the smoke is over 180 active wildfires in Ontario, 136 of them in the northwest. The fires have forced six First Nations communities to evacuate. Collins First Nation has suffered extensive damage, with its chief saying she is awaiting official confirmation that homes and community buildings have been lost.
