| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°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: | Sep. 21 - Sep. 30 | |
| Average Last Frost Date: | Jun. 1 - Jun. 10 | |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year | |
| Ecoregion: | 58q - Sunapee Uplands | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 03445 - Sullivan, NH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 8 | 10 | 20 | 31 | 42 | 51 | 55 | 54 | 45 | 34 | 26 | 15 | 33 |
| Avg Max Temp (°F) | 29 | 32 | 41 | 53 | 66 | 74 | 79 | 76 | 68 | 57 | 45 | 33 | 55 |
| Avg Precip (In.) | 3.58 | 2.75 | 3.5 | 3.57 | 4.09 | 3.87 | 4.11 | 4.19 | 3.6 | 3.82 | 3.75 | 3.39 | 44.21 |