Hunnewell, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.3 °C (low) to 17.7 °C (high). Annual precipitation averages 1040.1 Millimeters. Hunnewell 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.4 °C | 2.3 °C | 48.77 mm |
| February | -5.6 °C | 4.9 °C | 52.32 mm |
| March | -0.2 °C | 11.6 °C | 71.12 mm |
| April | 5.9 °C | 18.3 °C | 107.44 mm |
| May | 11.9 °C | 23.6 °C | 129.54 mm |
| June | 17.3 °C | 28.6 °C | 124.71 mm |
| July | 19.3 °C | 30.8 °C | 109.22 mm |
| August | 18.1 °C | 29.9 °C | 98.81 mm |
| September | 13.3 °C | 26.2 °C | 93.47 mm |
| October | 6.9 °C | 19.5 °C | 83.06 mm |
| November | 0.7 °C | 11.6 °C | 69.85 mm |
| December | -4.4 °C | 4.8 °C | 51.82 mm |
| Annual | 6.3 °C | 17.7 °C | 1040.13 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 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 |