Eureka, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 55.6 °F (low) to 77.1 °F (high). Annual precipitation averages 43 Inches. Eureka is located in USDA Plant Hardiness Zone 8b. 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 | 36.7 °F | 57.9 °F | 3.28 in. |
| February | 40.0 °F | 61.6 °F | 3.33 in. |
| March | 47.3 °F | 68.8 °F | 4.0 in. |
| April | 53.8 °F | 76.2 °F | 3.82 in. |
| May | 63.8 °F | 83.4 °F | 4.41 in. |
| June | 71.1 °F | 90.5 °F | 3.97 in. |
| July | 73.7 °F | 94.4 °F | 2.08 in. |
| August | 73.4 °F | 95.5 °F | 2.47 in. |
| September | 67.1 °F | 89.5 °F | 3.2 in. |
| October | 56.2 °F | 79.4 °F | 5.16 in. |
| November | 45.9 °F | 67.9 °F | 3.43 in. |
| December | 38.5 °F | 59.6 °F | 3.82 in. |
| Annual | 55.6 °F | 77.1 °F | 42.97 in. |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8a : 10°F to 15°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |