| 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. 11 - Oct. 20 | |
| Average Last Frost Date: | May 1 - May 10 | |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year | |
| 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 01420 - Fitchburg, MA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 13 | 15 | 24 | 34 | 44 | 54 | 59 | 57 | 49 | 37 | 29 | 19 | 36 |
| Avg Max Temp (°F) | 33 | 35 | 44 | 57 | 69 | 78 | 83 | 81 | 73 | 62 | 49 | 37 | 58 |
| Avg Precip (In.) | 3.98 | 3.02 | 4 | 3.92 | 3.73 | 3.73 | 3.78 | 4.06 | 3.74 | 4.08 | 4.2 | 3.8 | 46.03 |