Sarnia Weather Forecast

CURRENT CONDITIONS - July 31, 2025
17°
Low of16°
Feels like 17°CLast Updated: July 31, 2025 at 7:51 AMWeather information supplied by: OpenWeather API
POP:1%
Wind:10.19 km/h
Humidity:54%
UV:7.24
Sunrise:10:19 AM
Sunset:12:51 AM

Current Weather Alerts

Smoke is causing or expected to cause poor air quality and reduced visibility. Smoke from forest fires over the Prairies will affect southern Ontario tonight. Air quality and visibility due to wildfire smoke can fluctuate over short distances and can vary considerably from hour to hour. Air quality is expected to improve from north to south on Thursday. ### As smoke levels increase, health risks increase. Limit time outdoors. Consider reducing or rescheduling outdoor sports, activities and events. You may experience mild and common symptoms such as eye, nose and throat irritation, headaches or a mild cough. More serious but less common symptoms include wheezing, chest pains or severe cough. If you think you are having a medical emergency, seek immediate medical assistance. People more likely to be impacted by outdoor air pollution, including people aged 65 and older, pregnant people, infants and young children, people with an existing illness or chronic health condition, and people who work outdoors, should reduce or reschedule strenuous activities outdoors and seek medical attention if experiencing symptoms. Visit http://www.airhealth.ca for information on how to reduce your health risk and your personal contribution to pollution levels, as well as for current and forecast AQHI values. Please continue to monitor alerts and forecasts issued by Environment Canada.

Sarnia Weather Forecast - Hourly

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Sarnia Weather Forecast - Weekly

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Today
July 31
21°
16°
Tomorrow
August 1
21°
16°
Saturday
August 2
22°
14°
Sunday
August 3
26°
17°
Monday
August 4
28°
18°
Tuesday
August 5
28°
19°
Wednesday
August 6
29°
20°
Thursday
August 7
28°
20°

Local News

Wiarton. Photo by Janice MacKay

Wiarton Homecoming offers fun filled weekend

Wiarton is once again rolling out the welcome mat for residents and visitors with an exciting lineup of events for Homecoming Weekend 2025, running August 1st to 4th at 400 William Street.