Plantsville, Connecticut has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41 °F (low) to 60.8 °F (high). Annual precipitation averages 51.5 Inches. Plantsville is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 19.2 °F | 36.6 °F | 3.81 in. |
| February | 20.5 °F | 39.1 °F | 3.4 in. |
| March | 28.0 °F | 46.9 °F | 4.6 in. |
| April | 38.2 °F | 59.3 °F | 4.19 in. |
| May | 48.4 °F | 70.2 °F | 4.02 in. |
| June | 57.8 °F | 78.5 °F | 4.63 in. |
| July | 63.3 °F | 84.1 °F | 4.21 in. |
| August | 61.7 °F | 82.3 °F | 4.14 in. |
| September | 54.4 °F | 75.4 °F | 4.52 in. |
| October | 42.7 °F | 63.4 °F | 5.28 in. |
| November | 33.0 °F | 52.0 °F | 3.98 in. |
| December | 24.9 °F | 41.8 °F | 4.7 in. |
| Annual | 41 °F | 60.8 °F | 51.48 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |