| 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 5a: -20F to -15F | |
| Average First Frost Date: | Oct. 1 - Oct. 10 | |
| Average Last Frost Date: | May 21 - May 31 | |
| 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 03470 - Winchester, 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 | 35 | 28 | 17 | 34 |
| Avg Max Temp (°F) | 31 | 34 | 44 | 56 | 69 | 77 | 82 | 80 | 71 | 60 | 47 | 35 | 57 |
| Avg Precip (In.) | 3.48 | 2.61 | 3.43 | 3.42 | 3.43 | 3.69 | 3.89 | 3.7 | 3.45 | 3.62 | 3.61 | 3.3 | 41.63 |