Galt, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.1 °C (low) to 15.1 °C (high). Annual precipitation averages 996.4 Millimeters. Galt is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.5 °C | -1.4 °C | 43.18 mm |
| February | -8.4 °C | 1.1 °C | 43.94 mm |
| March | -2.6 °C | 8.1 °C | 60.96 mm |
| April | 3.4 °C | 15.7 °C | 97.79 mm |
| May | 10 °C | 22 °C | 124.71 mm |
| June | 15.4 °C | 27.1 °C | 135.89 mm |
| July | 17.2 °C | 28.7 °C | 108.46 mm |
| August | 16.1 °C | 27.7 °C | 108.46 mm |
| September | 11.4 °C | 24.5 °C | 94.74 mm |
| October | 4.9 °C | 17.3 °C | 71.12 mm |
| November | -1.3 °C | 8.8 °C | 57.66 mm |
| December | -6.9 °C | 1.7 °C | 49.53 mm |
| Annual | 4.1 °C | 15.1 °C | 996.44 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°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 |