| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Sep. 21 - Sep. 30 |
| Average Last Frost Date: | May 21 - May 31 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 58o - Northern Connecticut Valley |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 03608 - Walpole, NH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 9 | 11 | 22 | 33 | 44 | 53 | 58 | 56 | 47 | 36 | 28 | 16 | 34 |
| Avg Max Temp (°F) | 30 | 34 | 43 | 55 | 68 | 76 | 81 | 79 | 71 | 59 | 47 | 35 | 57 |
| Avg Precip (In.) | 3.28 | 2.44 | 3.17 | 3.2 | 3.67 | 3.42 | 3.79 | 3.76 | 3.18 | 3.44 | 3.43 | 3.04 | 39.81 |