| 2023 Hardiness Zone: | Zone 6b: -5°F to 0°F | |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F | |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F | |
| Average First Frost Date: | Oct. 11 - Oct. 20 | |
| Average Last Frost Date: | May 1 - May 10 | |
| 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 01752 - Marlborough, MA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 15 | 18 | 26 | 36 | 47 | 56 | 61 | 60 | 51 | 39 | 32 | 21 | 38 |
| Avg Max Temp (°F) | 34 | 37 | 46 | 57 | 69 | 78 | 83 | 81 | 73 | 62 | 50 | 39 | 59 |
| Avg Precip (In.) | 4.26 | 3.33 | 4.15 | 4.14 | 3.72 | 3.71 | 3.73 | 3.96 | 3.92 | 4.24 | 4.45 | 4.04 | 47.64 |