| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F |
| 2012 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 59h - Gulf of Maine Coastal Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 03064 - Nashua, NH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 12 | 15 | 25 | 34 | 45 | 54 | 59 | 57 | 49 | 37 | 29 | 19 | 36 |
| Avg Max Temp (°F) | 34 | 37 | 46 | 57 | 69 | 78 | 83 | 81 | 73 | 62 | 50 | 38 | 59 |
| Avg Precip (In.) | 3.85 | 3.06 | 4.01 | 3.91 | 3.65 | 3.85 | 3.68 | 3.73 | 3.64 | 3.96 | 4.18 | 3.74 | 45.27 |