| 2023 Hardiness Zone: | Zone 6b: -5°F to 0°F | |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F | |
| 1990 Hardiness Zone: | Zone 6a: -10F to -5F | |
| 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 06779 - Oakville, CT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 15 | 16 | 26 | 35 | 45 | 54 | 60 | 58 | 50 | 38 | 30 | 21 | 37 |
| Avg Max Temp (°F) | 35 | 37 | 47 | 58 | 70 | 78 | 83 | 81 | 73 | 62 | 51 | 39 | 59 |
| Avg Precip (In.) | 3.95 | 3.17 | 4.44 | 4.2 | 4.43 | 4.13 | 4.32 | 4.5 | 4.55 | 4.25 | 4.18 | 4.07 | 50.2 |