| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°F |
| 2012 Hardiness Zone: | Zone 4b: -25°F to -20°F |
| 1990 Hardiness Zone: | Zone 4a: -30F to -25F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 58k - Green Mountain Foothills |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 05494 - Westford, VT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 6 | 8 | 19 | 32 | 44 | 53 | 58 | 56 | 48 | 37 | 28 | 15 | 34 |
| Avg Max Temp (°F) | 26 | 28 | 39 | 52 | 67 | 75 | 80 | 77 | 68 | 56 | 43 | 31 | 53 |
| Avg Precip (In.) | 2.2 | 1.65 | 2.4 | 2.97 | 3.47 | 3.7 | 4.12 | 4.36 | 3.81 | 3.38 | 3.27 | 2.29 | 37.63 |