Concord, New Hampshire has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.6 °C (low) to 14.3 °C (high). Annual precipitation averages 1145 Millimeters. Concord 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 | -10.9 °C | -0.2 °C | 77.22 mm |
| February | -9.9 °C | 1.6 °C | 77.47 mm |
| March | -5 °C | 6.1 °C | 87.88 mm |
| April | 1.1 °C | 13.5 °C | 95.25 mm |
| May | 7.2 °C | 20.1 °C | 89.15 mm |
| June | 12.6 °C | 25.1 °C | 107.95 mm |
| July | 15.6 °C | 27.9 °C | 101.85 mm |
| August | 14.5 °C | 27.2 °C | 92.2 mm |
| September | 10.2 °C | 23 °C | 97.03 mm |
| October | 3.8 °C | 15.7 °C | 123.7 mm |
| November | -1.6 °C | 9.1 °C | 90.17 mm |
| December | -6.8 °C | 3 °C | 105.16 mm |
| Annual | 2.6 °C | 14.3 °C | 1145.03 mm |
| 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 : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |