| 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 |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 61c - Low Lime Drift Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 44654 - Millersburg, OH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 16 | 18 | 26 | 36 | 47 | 56 | 60 | 58 | 51 | 39 | 31 | 22 | 38 |
| Avg Max Temp (°F) | 34 | 38 | 49 | 60 | 71 | 79 | 83 | 81 | 75 | 63 | 50 | 39 | 60 |
| Avg Precip (In.) | 2.47 | 2.03 | 2.85 | 3.39 | 3.92 | 4.48 | 4.06 | 3.76 | 3.27 | 2.59 | 3.16 | 2.74 | 38.71 |