Troy, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 44.5 °F (low) to 65.4 °F (high). Annual precipitation averages 42.8 Inches. Troy 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 20.9 °F | 38.5 °F | 2.21 in. |
| February | 24.3 °F | 44.1 °F | 2.17 in. |
| March | 33.0 °F | 54.7 °F | 3.01 in. |
| April | 43.8 °F | 66.9 °F | 4.44 in. |
| May | 54.4 °F | 75.6 °F | 5.22 in. |
| June | 63.5 °F | 84.0 °F | 4.86 in. |
| July | 67.3 °F | 87.8 °F | 4.11 in. |
| August | 65.1 °F | 86.7 °F | 3.47 in. |
| September | 56.8 °F | 80.1 °F | 3.83 in. |
| October | 45.2 °F | 68.3 °F | 3.56 in. |
| November | 34.3 °F | 54.7 °F | 3.36 in. |
| December | 25.4 °F | 42.9 °F | 2.58 in. |
| Annual | 44.5 °F | 65.4 °F | 42.82 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 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 |