Milan, New Hampshire has a Subarctic With Cool Summers And Year Around Rainfall climate (Köppen classification: Dfc). Average annual temperatures range from 30.1 °F (low) to 52.3 °F (high). Annual precipitation averages 43.8 Inches. Milan is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.8 °F | 25.4 °F | 2.94 in. |
| February | 5.0 °F | 28.6 °F | 2.66 in. |
| March | 15.1 °F | 37.1 °F | 2.97 in. |
| April | 28.0 °F | 50.1 °F | 3.52 in. |
| May | 39.5 °F | 63.8 °F | 3.67 in. |
| June | 49.0 °F | 72.5 °F | 4.51 in. |
| July | 53.7 °F | 77.3 °F | 4.26 in. |
| August | 51.7 °F | 75.9 °F | 4.01 in. |
| September | 44.1 °F | 68.6 °F | 3.21 in. |
| October | 33.9 °F | 55.1 °F | 4.76 in. |
| November | 24.3 °F | 42.3 °F | 3.39 in. |
| December | 12.6 °F | 31.0 °F | 3.86 in. |
| Annual | 30.1 °F | 52.3 °F | 43.76 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfc - Subarctic With Cool Summers And Year Around Rainfall |