Caldwell, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 13.9 °C (low) to 26 °C (high). Annual precipitation averages 1010.7 Millimeters. Caldwell is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.9 °C | 15.9 °C | 85.85 mm |
| February | 5.9 °C | 17.9 °C | 67.31 mm |
| March | 9.4 °C | 21.8 °C | 93.98 mm |
| April | 13.3 °C | 25.6 °C | 64.52 mm |
| May | 18.3 °C | 29.4 °C | 122.68 mm |
| June | 21.9 °C | 33.1 °C | 82.3 mm |
| July | 23.1 °C | 34.7 °C | 42.42 mm |
| August | 22.8 °C | 35.4 °C | 63.75 mm |
| September | 19.9 °C | 32.4 °C | 81.28 mm |
| October | 14.3 °C | 27.3 °C | 121.92 mm |
| November | 8.7 °C | 21.4 °C | 88.9 mm |
| December | 4.8 °C | 16.9 °C | 95.76 mm |
| Annual | 13.9 °C | 26 °C | 1010.67 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°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 |