Plympton, Massachusetts has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 41.2 °F (low) to 60.1 °F (high). Annual precipitation averages 52.7 Inches. Plympton 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 | 20.1 °F | 37.9 °F | 4.46 in. |
| February | 21.4 °F | 39.8 °F | 4.01 in. |
| March | 28.3 °F | 46.3 °F | 5.68 in. |
| April | 37.6 °F | 57.1 °F | 4.71 in. |
| May | 47.3 °F | 67.2 °F | 3.73 in. |
| June | 56.7 °F | 76.3 °F | 3.93 in. |
| July | 63.1 °F | 82.4 °F | 3.5 in. |
| August | 61.6 °F | 80.9 °F | 3.68 in. |
| September | 54.5 °F | 74.1 °F | 4.08 in. |
| October | 43.5 °F | 62.9 °F | 5.02 in. |
| November | 34.1 °F | 52.8 °F | 4.67 in. |
| December | 26.0 °F | 43.3 °F | 5.22 in. |
| Annual | 41.2 °F | 60.1 °F | 52.69 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 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 | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |