Nortonville, Kentucky has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.3 °C (low) to 20.4 °C (high). Annual precipitation averages 1298.7 Millimeters. Nortonville 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 | -3.2 °C | 6.8 °C | 95.76 mm |
| February | -1.7 °C | 9.3 °C | 106.93 mm |
| March | 2.6 °C | 14.7 °C | 119.63 mm |
| April | 7.9 °C | 21.1 °C | 123.19 mm |
| May | 13.5 °C | 25.6 °C | 129.54 mm |
| June | 18.1 °C | 29.8 °C | 118.62 mm |
| July | 19.8 °C | 31.6 °C | 117.09 mm |
| August | 18.9 °C | 31.5 °C | 77.72 mm |
| September | 14.7 °C | 28.4 °C | 86.87 mm |
| October | 8.1 °C | 22.2 °C | 100.33 mm |
| November | 2.4 °C | 14.7 °C | 104.39 mm |
| December | -1.5 °C | 8.8 °C | 118.62 mm |
| Annual | 8.3 °C | 20.4 °C | 1298.69 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 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |