Plainville, Connecticut has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.8 °F (low) to 60.8 °F (high). Annual precipitation averages 52.4 Inches. Plainville is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.9 °F | 36.2 °F | 3.88 in. |
| February | 20.2 °F | 38.9 °F | 3.48 in. |
| March | 27.6 °F | 46.8 °F | 4.25 in. |
| April | 38.0 °F | 59.5 °F | 4.16 in. |
| May | 48.3 °F | 70.3 °F | 3.83 in. |
| June | 57.7 °F | 78.8 °F | 4.87 in. |
| July | 63.1 °F | 84.3 °F | 4.2 in. |
| August | 61.4 °F | 82.5 °F | 4.48 in. |
| September | 54.0 °F | 75.4 °F | 4.7 in. |
| October | 42.5 °F | 63.3 °F | 5.59 in. |
| November | 32.8 °F | 51.8 °F | 4.08 in. |
| December | 24.8 °F | 41.5 °F | 4.87 in. |
| Annual | 40.8 °F | 60.8 °F | 52.39 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 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 | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |