Buchanan Dam, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 55.3 °F (low) to 78.5 °F (high). Annual precipitation averages 28.3 Inches. Buchanan Dam 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 | 36.2 °F | 60.2 °F | 1.58 in. |
| February | 39.9 °F | 63.9 °F | 1.76 in. |
| March | 47.2 °F | 71.0 °F | 2.6 in. |
| April | 54.4 °F | 78.5 °F | 2.08 in. |
| May | 63.3 °F | 84.7 °F | 3.71 in. |
| June | 70.3 °F | 91.6 °F | 2.55 in. |
| July | 72.8 °F | 94.9 °F | 1.9 in. |
| August | 72.9 °F | 96.1 °F | 1.78 in. |
| September | 67.0 °F | 89.8 °F | 2.68 in. |
| October | 56.4 °F | 80.6 °F | 3.08 in. |
| November | 46.3 °F | 69.7 °F | 2.39 in. |
| December | 37.4 °F | 61.2 °F | 2.18 in. |
| Annual | 55.3 °F | 78.5 °F | 28.29 in. |
| 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 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |