Collinsville, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.6 °C (low) to 23.7 °C (high). Annual precipitation averages 1033.3 Millimeters. Collinsville is located in USDA Plant Hardiness Zone 8a. 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 | -0.1 °C | 12 °C | 56.9 mm |
| February | 1.9 °C | 14.4 °C | 68.83 mm |
| March | 6.2 °C | 18.8 °C | 91.69 mm |
| April | 10.6 °C | 23.3 °C | 92.71 mm |
| May | 16 °C | 27.3 °C | 133.1 mm |
| June | 20.8 °C | 32.1 °C | 103.12 mm |
| July | 23.1 °C | 34.8 °C | 64.26 mm |
| August | 22.6 °C | 35.1 °C | 66.04 mm |
| September | 18.4 °C | 30.8 °C | 88.14 mm |
| October | 12 °C | 24.9 °C | 113.79 mm |
| November | 6 °C | 18.3 °C | 76.45 mm |
| December | 1.2 °C | 13.1 °C | 78.23 mm |
| Annual | 11.6 °C | 23.7 °C | 1033.26 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°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 |