| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F | |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°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: | Dfa - Humid Continental Hot Summers | |
| Ecoregion: | 59c - Southern New England Coastal Plains and Hills | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 06751 - Bethlehem, CT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 13 | 15 | 24 | 34 | 44 | 53 | 59 | 57 | 49 | 38 | 29 | 20 | 36 |
| Avg Max Temp (°F) | 34 | 37 | 46 | 58 | 69 | 77 | 82 | 80 | 72 | 61 | 50 | 39 | 59 |
| Avg Precip (In.) | 4.21 | 3.17 | 4.56 | 4.29 | 4.64 | 4.31 | 4.55 | 4.6 | 4.77 | 4.53 | 4.36 | 4.15 | 52.12 |