Marion, Kentucky has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.5 °C (low) to 19.8 °C (high). Annual precipitation averages 1276.9 Millimeters. Marion is located in USDA Plant Hardiness Zone 7a. 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 | -3.3 °C | 6.2 °C | 96.27 mm |
| February | -1.9 °C | 8.7 °C | 96.01 mm |
| March | 2.6 °C | 14.1 °C | 122.17 mm |
| April | 8.2 °C | 20.3 °C | 128.78 mm |
| May | 13.6 °C | 24.9 °C | 136.14 mm |
| June | 18.2 °C | 29.4 °C | 114.05 mm |
| July | 20.1 °C | 31.2 °C | 113.28 mm |
| August | 18.9 °C | 30.9 °C | 75.95 mm |
| September | 14.9 °C | 28 °C | 85.6 mm |
| October | 8.6 °C | 21.2 °C | 92.2 mm |
| November | 2.8 °C | 14.1 °C | 105.66 mm |
| December | -1.2 °C | 8.2 °C | 110.74 mm |
| Annual | 8.5 °C | 19.8 °C | 1276.85 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 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 |