Potosi, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.1 °C (low) to 24.7 °C (high). Annual precipitation averages 680.5 Millimeters. Potosi is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.2 °C | 13.9 °C | 27.69 mm |
| February | 1.8 °C | 16.1 °C | 39.62 mm |
| March | 6.1 °C | 20.5 °C | 52.83 mm |
| April | 10.2 °C | 25.1 °C | 51.05 mm |
| May | 15.7 °C | 29.2 °C | 84.33 mm |
| June | 20.2 °C | 32.8 °C | 86.87 mm |
| July | 22 °C | 34.8 °C | 53.09 mm |
| August | 21.7 °C | 34.7 °C | 64.26 mm |
| September | 17.6 °C | 30.7 °C | 76.71 mm |
| October | 11.6 °C | 25.6 °C | 68.83 mm |
| November | 5.3 °C | 19.1 °C | 41.15 mm |
| December | 0.8 °C | 14.4 °C | 34.04 mm |
| Annual | 11.1 °C | 24.7 °C | 680.47 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| 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 |