Clayton, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.1 °C (low) to 16.5 °C (high). Annual precipitation averages 1135.1 Millimeters. Clayton is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.9 °C | 1.8 °C | 77.72 mm |
| February | -5.4 °C | 4.1 °C | 66.04 mm |
| March | -0.4 °C | 10.2 °C | 86.11 mm |
| April | 5.6 °C | 16.8 °C | 120.14 mm |
| May | 11.6 °C | 22.3 °C | 122.43 mm |
| June | 16.4 °C | 27.1 °C | 132.33 mm |
| July | 18.2 °C | 28.8 °C | 114.55 mm |
| August | 17.3 °C | 28.2 °C | 80.52 mm |
| September | 13.1 °C | 25.2 °C | 89.15 mm |
| October | 6.8 °C | 18.3 °C | 87.88 mm |
| November | 0.8 °C | 10.6 °C | 83.06 mm |
| December | -4.1 °C | 4.2 °C | 75.18 mm |
| Annual | 6.1 °C | 16.5 °C | 1135.11 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |