St Marys, in Ontario, Canada, is home to roughly 7,400 people in the Eastern Time Zone at 43.3°N latitude.
In 2025, St Marys recorded an average annual temperature of 46°F. The hottest temperatures reached 90°F in June; the coolest were -10°F in January. Total precipitation for the year was 38 inches, with the wettest month being December. Snowfall for the year totaled approximately 33 inches.
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