Gilford, New Hampshire has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.8 °C (low) to 11.5 °C (high). Annual precipitation averages 1352.3 Millimeters. Gilford 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.6 °C | -2.7 °C | 84.84 mm |
| February | -11.4 °C | -1.2 °C | 97.03 mm |
| March | -7 °C | 3.3 °C | 99.82 mm |
| April | -1.1 °C | 10.6 °C | 102.11 mm |
| May | 4.7 °C | 17.4 °C | 100.58 mm |
| June | 10 °C | 22 °C | 134.37 mm |
| July | 12.9 °C | 24.9 °C | 125.73 mm |
| August | 12.2 °C | 24 °C | 108.71 mm |
| September | 8.4 °C | 20 °C | 117.09 mm |
| October | 2.7 °C | 12.7 °C | 148.08 mm |
| November | -2.8 °C | 6 °C | 113.03 mm |
| December | -7.9 °C | 0.4 °C | 120.9 mm |
| Annual | 0.8 °C | 11.5 °C | 1352.29 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |