| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F Zone 7a: 0°F to 5°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 70d - Knobs-Lower Scioto Dissected Plateau |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 45601 - Chillicothe, OH | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 18 | 21 | 30 | 39 | 50 | 59 | 63 | 61 | 53 | 41 | 33 | 24 | 41 |
| Avg Max Temp (°F) | 37 | 42 | 53 | 63 | 73 | 81 | 85 | 84 | 78 | 66 | 53 | 42 | 63 |
| Avg Precip (In.) | 2.71 | 2.51 | 3.51 | 3.49 | 4.38 | 4.03 | 3.93 | 3.93 | 2.98 | 2.54 | 3.11 | 2.9 | 40.01 |