Stewartsville, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.2 °F (low) to 63.5 °F (high). Annual precipitation averages 38.9 Inches. Stewartsville 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 | 16.7 °F | 35.9 °F | 0.94 in. |
| February | 20.4 °F | 41.2 °F | 1.32 in. |
| March | 30.9 °F | 53.2 °F | 2.42 in. |
| April | 40.8 °F | 63.9 °F | 3.77 in. |
| May | 52.4 °F | 73.7 °F | 5.51 in. |
| June | 62.2 °F | 82.9 °F | 5.32 in. |
| July | 66.4 °F | 87.3 °F | 4.85 in. |
| August | 64.3 °F | 85.8 °F | 4.3 in. |
| September | 55.2 °F | 78.6 °F | 3.82 in. |
| October | 43.2 °F | 66.4 °F | 3.18 in. |
| November | 31.8 °F | 52.8 °F | 1.93 in. |
| December | 21.8 °F | 40.2 °F | 1.56 in. |
| Annual | 42.2 °F | 63.5 °F | 38.92 in. |
| 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 : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |