Llano, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.5 °C (low) to 26.4 °C (high). Annual precipitation averages 677.4 Millimeters. Llano 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. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 0.3 °C | 16.2 °C | 37.85 mm |
| February | 2.7 °C | 18.3 °C | 41.4 mm |
| March | 6.7 °C | 22.1 °C | 62.74 mm |
| April | 10.9 °C | 26.3 °C | 51.05 mm |
| May | 16.4 °C | 29.8 °C | 95.5 mm |
| June | 20.4 °C | 33.7 °C | 71.12 mm |
| July | 21.6 °C | 35.6 °C | 39.88 mm |
| August | 21.6 °C | 36.2 °C | 40.13 mm |
| September | 18.2 °C | 32.6 °C | 58.42 mm |
| October | 11.6 °C | 27.4 °C | 75.95 mm |
| November | 5.9 °C | 21.3 °C | 53.59 mm |
| December | 1.2 °C | 16.7 °C | 49.78 mm |
| Annual | 11.5 °C | 26.4 °C | 677.41 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| 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 |