Galveston, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.3 °C (low) to 16 °C (high). Annual precipitation averages 1049 Millimeters. Galveston is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.7 °C | 0.7 °C | 67.06 mm |
| February | -6.3 °C | 2.8 °C | 56.13 mm |
| March | -1.4 °C | 9.1 °C | 72.39 mm |
| April | 4.3 °C | 16.2 °C | 97.54 mm |
| May | 10.8 °C | 22.3 °C | 112.27 mm |
| June | 16.1 °C | 27.1 °C | 127.51 mm |
| July | 17.6 °C | 28.7 °C | 118.11 mm |
| August | 16.3 °C | 27.9 °C | 97.28 mm |
| September | 12.2 °C | 25.1 °C | 82.8 mm |
| October | 6 °C | 18.1 °C | 76.2 mm |
| November | 0.5 °C | 10.1 °C | 78.99 mm |
| December | -4.4 °C | 3.4 °C | 62.74 mm |
| Annual | 5.3 °C | 16 °C | 1049.02 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |