About Iona, ID's Climate & Weather History

Iona is a city of approximately 2,100 people in Idaho, United States. Located in the America/Boise time zone at 43.5°N latitude.

In 2025, Iona recorded an average annual temperature of 48°F — about 3.7°F above the 30-year normal of 44°F. The hottest day reached 96°F in August; the coldest was -19°F in January. Total precipitation was 13 inches (wetter than usual). The wettest month was October.