Petersburg, Tennessee has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.5 °C (low) to 21.5 °C (high). Annual precipitation averages 1520.5 Millimeters. Petersburg is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.9 °C | 9.3 °C | 130.3 mm |
| February | -0.4 °C | 11.8 °C | 133.6 mm |
| March | 3.3 °C | 16.7 °C | 144.27 mm |
| April | 7.6 °C | 21.9 °C | 133.35 mm |
| May | 12.9 °C | 26.2 °C | 125.73 mm |
| June | 17.4 °C | 30.2 °C | 131.57 mm |
| July | 19.6 °C | 31.8 °C | 140.21 mm |
| August | 18.8 °C | 31.7 °C | 111.51 mm |
| September | 14.8 °C | 28.8 °C | 111.51 mm |
| October | 8.2 °C | 23 °C | 95.76 mm |
| November | 2.5 °C | 16.2 °C | 104.14 mm |
| December | -0.4 °C | 10.9 °C | 158.5 mm |
| Annual | 8.5 °C | 21.5 °C | 1520.45 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |