Calvert City, Kentucky has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9 °C (low) to 20.6 °C (high). Annual precipitation averages 1316.2 Millimeters. Calvert City is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -2.8 °C | 6.9 °C | 103.38 mm |
| February | -1.2 °C | 9.5 °C | 99.31 mm |
| March | 3.2 °C | 15.1 °C | 120.9 mm |
| April | 8.5 °C | 21.4 °C | 130.3 mm |
| May | 14 °C | 25.9 °C | 140.72 mm |
| June | 18.8 °C | 30.4 °C | 115.32 mm |
| July | 20.9 °C | 32.3 °C | 108.46 mm |
| August | 19.7 °C | 31.9 °C | 82.8 mm |
| September | 15.3 °C | 28.4 °C | 87.88 mm |
| October | 9 °C | 22.1 °C | 97.54 mm |
| November | 3.1 °C | 14.7 °C | 107.95 mm |
| December | -1 °C | 8.8 °C | 121.67 mm |
| Annual | 9 °C | 20.6 °C | 1316.23 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |