Keytesville, 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 17.8 °C (high). Annual precipitation averages 1031 Millimeters. Keytesville 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 | -7.7 °C | 2.7 °C | 36.58 mm |
| February | -5.3 °C | 5.6 °C | 47.75 mm |
| March | 0.1 °C | 11.9 °C | 70.1 mm |
| April | 5.9 °C | 18.2 °C | 104.39 mm |
| May | 12.1 °C | 23.4 °C | 137.67 mm |
| June | 17.6 °C | 28.4 °C | 132.59 mm |
| July | 19.6 °C | 30.6 °C | 116.59 mm |
| August | 18.2 °C | 30 °C | 98.3 mm |
| September | 13.2 °C | 26.2 °C | 92.2 mm |
| October | 6.7 °C | 19.6 °C | 83.57 mm |
| November | 0.4 °C | 11.8 °C | 65.02 mm |
| December | -4.8 °C | 5.1 °C | 46.23 mm |
| Annual | 6.3 °C | 17.8 °C | 1030.99 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |