| 2023 Hardiness Zone: | Zone 6b: -5°F to 0°F Zone 7a: 0°F to 5°F | |
| 2012 Hardiness Zone: | Zone 6b: -5°F to 0°F Zone 7a: 0°F to 5°F | |
| 1990 Hardiness Zone: | Zone 6b: -5F to 0F | |
| Average First Frost Date: | Oct. 11 - Oct. 20 | |
| Average Last Frost Date: | Apr. 21 - Apr. 30 | |
| 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 06897 - Wilton, CT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 19 | 21 | 29 | 38 | 47 | 56 | 62 | 61 | 53 | 41 | 34 | 24 | 40 |
| Avg Max Temp (°F) | 37 | 39 | 48 | 60 | 71 | 79 | 84 | 82 | 74 | 63 | 52 | 41 | 61 |
| Avg Precip (In.) | 4.34 | 3.23 | 4.61 | 4.5 | 4.84 | 4.17 | 4.06 | 4.22 | 4.56 | 4.25 | 4.51 | 4.17 | 51.45 |