| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 21 - May 31 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 59a - Connecticut Valley |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 01360 - Northfield, MA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 10 | 13 | 23 | 33 | 44 | 53 | 58 | 56 | 48 | 37 | 29 | 18 | 35 |
| Avg Max Temp (°F) | 32 | 35 | 45 | 57 | 70 | 78 | 83 | 81 | 72 | 61 | 48 | 36 | 58 |
| Avg Precip (In.) | 3.14 | 2.4 | 3.15 | 3.16 | 3.27 | 3.34 | 3.91 | 3.57 | 3.22 | 3.34 | 3.26 | 2.98 | 38.74 |