Clay City, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.4 °C (low) to 17.6 °C (high). Annual precipitation averages 1171 Millimeters. Clay City 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 | -6.3 °C | 2.7 °C | 83.06 mm |
| February | -4.7 °C | 5.6 °C | 65.28 mm |
| March | 0.2 °C | 11.4 °C | 88.65 mm |
| April | 6.2 °C | 18.1 °C | 128.02 mm |
| May | 11.8 °C | 23.6 °C | 124.97 mm |
| June | 16.7 °C | 28.2 °C | 127.76 mm |
| July | 18.4 °C | 29.7 °C | 112.78 mm |
| August | 17.3 °C | 29.2 °C | 77.72 mm |
| September | 13 °C | 26.2 °C | 91.95 mm |
| October | 6.7 °C | 19.5 °C | 93.47 mm |
| November | 1 °C | 11.8 °C | 96.01 mm |
| December | -3.6 °C | 5.2 °C | 81.28 mm |
| Annual | 6.4 °C | 17.6 °C | 1170.95 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 |