New Salem, Massachusetts has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.6 °F (low) to 57.5 °F (high). Annual precipitation averages 54.4 Inches. New Salem is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 12.2 °F | 32.0 °F | 3.99 in. |
| February | 13.4 °F | 35.0 °F | 3.57 in. |
| March | 22.0 °F | 43.1 °F | 4.34 in. |
| April | 33.0 °F | 56.3 °F | 4.34 in. |
| May | 43.8 °F | 67.7 °F | 4.0 in. |
| June | 53.2 °F | 76.5 °F | 5.12 in. |
| July | 58.8 °F | 82.0 °F | 4.56 in. |
| August | 56.6 °F | 80.4 °F | 5.07 in. |
| September | 48.7 °F | 72.8 °F | 5.09 in. |
| October | 37.6 °F | 59.5 °F | 5.32 in. |
| November | 28.3 °F | 47.8 °F | 4.12 in. |
| December | 19.3 °F | 37.3 °F | 4.83 in. |
| Annual | 35.6 °F | 57.5 °F | 54.35 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |