About Marion, OH's Climate & Weather History

With a population of around 36,400, Marion sits in Ohio, United States. The city operates in the Eastern Time Zone.

In 2025, Marion recorded an average annual temperature of 51°F — about 0.5°F above the 30-year normal of 51°F. The hottest day reached 93°F in June; the coldest was -9°F in January. Total precipitation was 41 inches (wetter than usual). The wettest month was May.