Fairfield, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 13 °C (low) to 25.4 °C (high). Annual precipitation averages 1122.2 Millimeters. Fairfield is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.8 °C | 14.9 °C | 84.58 mm |
| February | 4.7 °C | 17.2 °C | 86.61 mm |
| March | 8.4 °C | 20.9 °C | 99.31 mm |
| April | 12.2 °C | 25.2 °C | 95 mm |
| May | 17.3 °C | 28.8 °C | 117.09 mm |
| June | 21.4 °C | 32.8 °C | 106.43 mm |
| July | 22.8 °C | 34.9 °C | 51.56 mm |
| August | 22.4 °C | 35.6 °C | 70.61 mm |
| September | 19 °C | 32.1 °C | 95.5 mm |
| October | 13.2 °C | 26.7 °C | 118.36 mm |
| November | 7.8 °C | 20.4 °C | 96.77 mm |
| December | 3.6 °C | 15.8 °C | 100.33 mm |
| Annual | 13 °C | 25.4 °C | 1122.15 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |