Hardin, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6 °C (low) to 18.1 °C (high). Annual precipitation averages 1072.1 Millimeters. Hardin is located in USDA Plant Hardiness Zone 6a. 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 | -7.7 °C | 3.2 °C | 36.58 mm |
| February | -5.4 °C | 6.3 °C | 47.24 mm |
| March | -0.2 °C | 12.4 °C | 70.61 mm |
| April | 5.6 °C | 18.5 °C | 106.93 mm |
| May | 11.6 °C | 23.9 °C | 140.97 mm |
| June | 17.1 °C | 28.7 °C | 135.13 mm |
| July | 19.3 °C | 30.9 °C | 121.16 mm |
| August | 17.9 °C | 30.3 °C | 111 mm |
| September | 12.9 °C | 26.1 °C | 111 mm |
| October | 6.3 °C | 19.8 °C | 86.36 mm |
| November | 0.2 °C | 11.9 °C | 60.2 mm |
| December | -5.1 °C | 5.5 °C | 44.96 mm |
| Annual | 6 °C | 18.1 °C | 1072.14 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |