Newton, New Hampshire has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 38.2 °F (low) to 59 °F (high). Annual precipitation averages 48.3 Inches. Newton is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 15.9 °F | 34.6 °F | 3.56 in. |
| February | 17.6 °F | 37.3 °F | 3.47 in. |
| March | 25.1 °F | 44.8 °F | 4.57 in. |
| April | 35.3 °F | 57.4 °F | 4.23 in. |
| May | 45.4 °F | 67.7 °F | 3.88 in. |
| June | 55.0 °F | 76.9 °F | 4.26 in. |
| July | 60.7 °F | 82.6 °F | 3.58 in. |
| August | 58.8 °F | 81.2 °F | 3.51 in. |
| September | 51.4 °F | 73.9 °F | 3.87 in. |
| October | 39.8 °F | 61.5 °F | 4.93 in. |
| November | 30.9 °F | 50.5 °F | 3.85 in. |
| December | 22.4 °F | 40.0 °F | 4.61 in. |
| Annual | 38.2 °F | 59 °F | 48.32 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |