Grand River South, in Ontario, Canada, is home to roughly 9,600 people in the Eastern Time Zone at 43.5°N latitude.
In 2025, Grand River South recorded an average annual temperature of 46°F. The hottest temperatures reached 93°F in June; the coolest were -9°F in January. Total precipitation for the year was 31 inches, with the wettest month being December. Snowfall for the year totaled approximately 24 inches.
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