Milton Mills, New Hampshire has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 36.7 °F (low) to 56.8 °F (high). Annual precipitation averages 49.3 Inches. Milton Mills 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 | 13.0 °F | 30.7 °F | 3.45 in. |
| February | 13.9 °F | 33.7 °F | 3.53 in. |
| March | 22.4 °F | 41.9 °F | 4.16 in. |
| April | 33.4 °F | 55.5 °F | 4.26 in. |
| May | 44.6 °F | 67.4 °F | 3.72 in. |
| June | 54.2 °F | 76.3 °F | 4.45 in. |
| July | 59.8 °F | 81.7 °F | 4.15 in. |
| August | 58.3 °F | 80.0 °F | 3.88 in. |
| September | 50.7 °F | 72.1 °F | 3.85 in. |
| October | 39.6 °F | 59.1 °F | 5.07 in. |
| November | 29.8 °F | 47.0 °F | 4.17 in. |
| December | 20.4 °F | 36.3 °F | 4.59 in. |
| Annual | 36.7 °F | 56.8 °F | 49.28 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |