Rockville, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 45.4 °F (low) to 67.2 °F (high). Annual precipitation averages 44.4 Inches. Rockville 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 | 21.6 °F | 41.7 °F | 1.75 in. |
| February | 25.2 °F | 46.8 °F | 2.02 in. |
| March | 34.5 °F | 57.1 °F | 3.05 in. |
| April | 44.3 °F | 67.4 °F | 4.7 in. |
| May | 55.1 °F | 76.0 °F | 6.07 in. |
| June | 64.7 °F | 84.9 °F | 5.25 in. |
| July | 68.7 °F | 89.8 °F | 4.45 in. |
| August | 66.5 °F | 88.8 °F | 3.88 in. |
| September | 57.8 °F | 81.3 °F | 4.35 in. |
| October | 45.7 °F | 70.1 °F | 3.43 in. |
| November | 35.0 °F | 56.6 °F | 3.11 in. |
| December | 26.0 °F | 45.4 °F | 2.37 in. |
| Annual | 45.4 °F | 67.2 °F | 44.43 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 |