Blanco, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.6 °C (low) to 25.3 °C (high). Annual precipitation averages 879.8 Millimeters. Blanco 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 | 2.7 °C | 15.7 °C | 59.94 mm |
| February | 4.7 °C | 17.7 °C | 50.29 mm |
| March | 8.4 °C | 21.4 °C | 70.1 mm |
| April | 12.1 °C | 25.3 °C | 67.82 mm |
| May | 17.1 °C | 28.7 °C | 121.67 mm |
| June | 20.5 °C | 32.2 °C | 73.15 mm |
| July | 21.6 °C | 33.8 °C | 53.59 mm |
| August | 21.5 °C | 34.6 °C | 59.18 mm |
| September | 18.3 °C | 31.2 °C | 91.44 mm |
| October | 13.2 °C | 26.5 °C | 96.01 mm |
| November | 7.7 °C | 20.4 °C | 77.72 mm |
| December | 3.5 °C | 16.4 °C | 58.93 mm |
| Annual | 12.6 °C | 25.3 °C | 879.84 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 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |