Chaplin, Connecticut has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4.1 °C (low) to 15.5 °C (high). Annual precipitation averages 1274.3 Millimeters. Chaplin 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 | -7.8 °C | 2.4 °C | 99.57 mm |
| February | -7.2 °C | 3.8 °C | 85.09 mm |
| March | -3.1 °C | 8 °C | 117.09 mm |
| April | 2.4 °C | 14.8 °C | 112.78 mm |
| May | 8 °C | 20.6 °C | 90.42 mm |
| June | 13.1 °C | 25 °C | 106.68 mm |
| July | 16.5 °C | 27.8 °C | 102.36 mm |
| August | 15.4 °C | 26.9 °C | 106.17 mm |
| September | 11.3 °C | 23.3 °C | 108.46 mm |
| October | 5.1 °C | 16.9 °C | 124.46 mm |
| November | -0.2 °C | 10.9 °C | 103.38 mm |
| December | -4.5 °C | 5.3 °C | 117.86 mm |
| Annual | 4.1 °C | 15.5 °C | 1274.32 mm |
| 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 : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |