Jamestown, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 44.9 °F (low) to 65.1 °F (high). Annual precipitation averages 43 Inches. Jamestown is located in USDA Plant Hardiness Zone 6b. 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 | 21.0 °F | 39.0 °F | 2.14 in. |
| February | 24.9 °F | 44.4 °F | 2.18 in. |
| March | 34.0 °F | 55.3 °F | 3.06 in. |
| April | 44.1 °F | 66.0 °F | 4.82 in. |
| May | 54.6 °F | 74.9 °F | 5.06 in. |
| June | 63.9 °F | 83.4 °F | 4.51 in. |
| July | 67.8 °F | 87.6 °F | 4.47 in. |
| August | 65.7 °F | 87.0 °F | 3.81 in. |
| September | 57.4 °F | 79.6 °F | 4.15 in. |
| October | 45.6 °F | 67.7 °F | 3.56 in. |
| November | 34.7 °F | 54.1 °F | 2.98 in. |
| December | 25.6 °F | 42.6 °F | 2.26 in. |
| Annual | 44.9 °F | 65.1 °F | 43 in. |
| 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 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |