| 2023 Hardiness Zone: | Zone 4b: -25°F to -20°F |
| 2012 Hardiness Zone: | Zone 4b: -25°F to -20°F Zone 4a: -30°F to -25°F |
| 1990 Hardiness Zone: | Zone 4a: -30F to -25F |
| Average First Frost Date: | Sep. 21 - Sep. 30 |
| Average Last Frost Date: | Jun. 1 - Jun. 10 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 58l - Northern Piedmont |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 05819 - Saint Johnsbury, VT | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 5 | 6 | 18 | 30 | 42 | 51 | 56 | 54 | 46 | 35 | 27 | 12 | 32 |
| Avg Max Temp (°F) | 26 | 30 | 41 | 54 | 68 | 76 | 80 | 77 | 68 | 56 | 42 | 30 | 54 |
| Avg Precip (In.) | 2.87 | 2.08 | 2.63 | 2.79 | 3.41 | 3.98 | 3.95 | 4.28 | 3.52 | 3.33 | 3.38 | 3.08 | 39.28 |