Sarnia Weather Forecast

Multi-day heat event continues. What: Daytime highs of 30 to 35 degrees Celsius, with humidex values of 35 to 40. Overnight lows of 19 to 22 degrees Celsius. When: Continuing through Tuesday or possibly Wednesday for some areas. Additional information: Slightly cooler temperatures are expected by Wednesday, bringing an end to this heat event. Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high risk category. ### Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion. For more information: https://www.canada.ca/en/health-canada/services/climate-change-health/extreme-heat/how-protect-yourself.html https://www.canada.ca/en/health-canada/services/climate-change-health/extreme-heat/who-is-at-risk.html Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to ONstorm@ec.gc.ca or post reports on X using #ONStorm.