| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5b: -15°F to -10°F | |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F 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: | Oct. 1 - Oct. 10 | |
| Average Last Frost Date: | May 11 - May 20 | |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year | |
| Ecoregion: | 58g - Worcester/Monadnock Plateau | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 03242 - Henniker, NH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 10 | 12 | 22 | 32 | 43 | 52 | 57 | 55 | 47 | 36 | 28 | 16 | 34 |
| Avg Max Temp (°F) | 30 | 33 | 42 | 55 | 67 | 75 | 80 | 78 | 69 | 58 | 46 | 34 | 56 |
| Avg Precip (In.) | 3.62 | 3.04 | 3.82 | 3.7 | 4 | 3.59 | 3.6 | 3.73 | 3.63 | 3.92 | 4.03 | 3.69 | 44.36 |