Millsap, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12 °C (low) to 25.2 °C (high). Annual precipitation averages 851.9 Millimeters. Millsap is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 0.6 °C | 14.3 °C | 47.24 mm |
| February | 2.6 °C | 16.2 °C | 59.44 mm |
| March | 6.9 °C | 20.6 °C | 76.2 mm |
| April | 11.2 °C | 25 °C | 71.37 mm |
| May | 16.8 °C | 28.8 °C | 107.44 mm |
| June | 21.2 °C | 33.1 °C | 91.44 mm |
| July | 23.1 °C | 35.7 °C | 49.78 mm |
| August | 22.7 °C | 35.8 °C | 64.26 mm |
| September | 18.6 °C | 31.8 °C | 74.42 mm |
| October | 12.3 °C | 26.2 °C | 95.76 mm |
| November | 6.3 °C | 19.6 °C | 61.98 mm |
| December | 1.6 °C | 14.9 °C | 52.58 mm |
| Annual | 12 °C | 25.2 °C | 851.91 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |