| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°F |
| 1990 Hardiness Zone: | Zone 4b: -25F to -20F |
| Average First Frost Date: | Sep. 21 - Sep. 30 |
| Average Last Frost Date: | May 21 - May 31 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 82e - Central Maine Embayment |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 04360 - Vienna, ME | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 5 | 8 | 19 | 30 | 40 | 50 | 55 | 54 | 45 | 35 | 26 | 13 | 32 |
| Avg Max Temp (°F) | 27 | 30 | 39 | 51 | 65 | 74 | 79 | 77 | 68 | 57 | 43 | 32 | 54 |
| Avg Precip (In.) | 3.66 | 2.74 | 3.84 | 3.92 | 4.03 | 4.32 | 3.62 | 3.87 | 3.8 | 4.18 | 4.15 | 3.82 | 45.94 |