Galena, Indiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.5 °C (low) to 18.9 °C (high). Annual precipitation averages 1252.7 Millimeters. Galena is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.4 °C | 5.1 °C | 94.23 mm |
| February | -3 °C | 7.7 °C | 87.12 mm |
| March | 1.3 °C | 13.2 °C | 110.24 mm |
| April | 6.8 °C | 19.6 °C | 130.05 mm |
| May | 12.6 °C | 24.3 °C | 136.91 mm |
| June | 17.2 °C | 28.6 °C | 120.9 mm |
| July | 19.2 °C | 30.3 °C | 102.36 mm |
| August | 18.4 °C | 29.9 °C | 81.03 mm |
| September | 14.2 °C | 26.8 °C | 94.49 mm |
| October | 7.7 °C | 20.4 °C | 93.98 mm |
| November | 1.9 °C | 13.3 °C | 93.73 mm |
| December | -2.1 °C | 7.2 °C | 107.7 mm |
| Annual | 7.5 °C | 18.9 °C | 1252.74 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |